Category: Uncategorized

Introduction

Illegal immigration is one of the main topics that have dominated debates across the United States for several decades. The federal government defines illegal immigration as the situation where a foreigner acts in disregard to the countrys immigration laws by either gaining entry into the United States without a visa or choosing to remain in the country beyond the expiry date of a temporary permit (Haines 16). According to the Department of Homeland Security (DHS), there are more than 15 million illegal immigrants living in the United States. The biggest percentage of the immigrant population in the country constitutes of Mexicans. The others come from Central America, Asia, Africa, South America, Europe, the Caribbean, and Canada (Varsanyi 209). Illegal immigration has been a cause of disagreement among policy makers and the public owing to the fact that the number of unauthorized residents keeps increasing every year.

The growing trend of illegal immigration in the United States is worrying because the country has one of the most complex and active immigration systems. Over the years, this topic has been a hotly contested issue in presidential campaigns, as various candidates present their proposals to the electorate on the most effective approach they would use to address the challenge (Berry 18). For example, in the ongoing 2016 presidential campaigns, many candidates participating in the party primaries have been criticized for their positions with regard to this growing policy issue. For example, Rick Perry is one of the candidates running to secure the Republican presidential ticket. He argues that the growing size of the illegal immigrant population in the country is largely attributable to the laxity shown by the federal immigration agents with regard to accepting the reality on the ground and coming up with effective strategies for addressing the issue.

Discussion

One of the main challenges the federal government faces in dealing with this situation is establishing the actual size and composition of the illegal immigrant population in the country (Varsanyi 223). Although the United States border patrol agents argue that the problem of illegal immigration is not widely spread, they have been challenged to concur with its reality. Information gathered through numerous surveys indicates that there are approximately more than 10 million illegal immigrants living in the country (Haines 21). However, the population size of illegal immigrants in the country has stabilized a lot over the last couple of years. One of the main factors that have influenced the decline is the global financial crisis that resulted in the reduction of job opportunities by a great margin. In 2012, a report released by Pew Research Center showed the population of illegal immigrants to be slightly over 11 million, which was a decline from the 12.2 million they had reported five years earlier (Haines 24).

The report also indicated that 28% of the population constituted of Mexicans who also had the highest percentage in the list of people waiting for their visas to be approved (Borjas 195). However, this number is just a rough estimate because immigration agents manage to apprehend close to 50,000 people every year as they attempt to enter the country illegally. Most of those apprehended are unaccompanied minors and women. A 2014 federal report on illegal immigration indicated that most of the illegal immigrants apprehended get into the country in order to reunite with their family members already living in the country, while others are motivated by a desire to attain a more stable livelihood (Berry 60). There is a growing concern that the number of illegal immigrants in the country is very high compared to that of legal immigrants. This phenomenon has been created by the strict immigration policies laid out by the federal government, thus barring foreigners with a desire to reside or work on the United States (Varsanyi 236).

The trends exhibited by illegal immigrants moving into the United States have changed a lot over the years. Initially, most of the foreigners who entered and remained in the country illegally lived in areas with Hispanic communities (Laham 116). However, this trend has changed a lot since the turn of the century because most illegal immigrants have managed to settle within various communities across the country. A report released by the federal government in 2006 indicated that the state of California had the highest number of illegal immigrants followed by the states of Texas, Florida, Illinois, New York, Arizona, Georgia, New Jersey, North Carolina, and Washington respectively (Borjas 207).

In 1990s, most illegal immigrants in the country had small families because they could not manage to support one without meaningful income. However, a report released in 2012 indicated that millions of people living in the country belonged to families that were headed by an illegal immigrant (Haines 39). Most of the illegal immigrants who gained entry into the United States after the turn of the century have managed to get jobs because they are educated. Unlike those that came into the country before, most of the 21^st Century illegal immigrants have college education that has enabled them secure employment (Berry 71). They work in various sectors of the countrys economy such as agriculture, service industries, and construction. Their income bracket is very low compared to that of legal immigrants and Native Americans. However, the longer one stays in the country the better chance they have of earning more (Laham 123). It is also important to note that the illegal immigrant population is generally less educated compared to the Native American population.

Causes of the illegal immigration challenge in the United States

According to international relations experts, the United States ranks as one of the most desirable countries to live in because of its strong economy, prolonged political stability, and social environment (Laham 132). Most people that have immigrated to the country argue that they moved away from their native countries in search for better jobs, freedom, a serene political environment, good medical services, and increased access to education (Heron 31). These elements have played a major role in attracting foreigners seeking a chance at a better life and a secure future. However, most of the foreigners who have made their way into the United States over the years used illegal means. According to various federal reports, 5 % of the American labor force constitutes of illegal immigrants, especially in the states of Nevada, California, and Texas (Varsanyi 269). A number of factors are responsible for the emergence and the continued growing trend of illegal immigration in the country. They include geopolitical forces, economic incentives, the countrys immigration system, and the network effect.

Geopolitical forces attribute to a great share of illegal immigrants that come to the United States every year. For example, most of the immigrants that come from Mexico attribute the harsh political environment characterized by oppression and harassment by government officials as their reason for choosing to move into the United States (Heron 36). Such an environment easily pushes someone to use illegal means to cross the American border, especially when they know their visa might take long to be accepted or it might be declined. This normally happens because of a certain reasons as stipulated in the countrys immigration and customs law. Illegal immigrants from Asia and Africa also attribute lack of political will with regard to development of policies for economic empowerment and social development as their main reason for moving to the United States (Laham 140).

Poor development and implementation of social policies has forced many people from these two regions to illegally, make their way into the country where they work as commercial sex workers, indentured servants, and in some unfortunate cases as sex slaves (Varsanyi 300). Most illegal immigrants who come from Europe and the Middle East move to the United States in search for a better future, as well as the need to link up with family members already settled in the country (Heron 40). In countries such as Mexico and some from the Asian continent where the fertility rate is very high, a rapid growth in population over the years has created a huge strain on the available resources, thus making the future very unpredictable (Haines 52). This phenomenon coupled with a lack of political with regard to coming up with effective policies on sustainable development have made many people to move to the United States in search for better opportunities (Berry 100).

Economic incentives are also a major cause of illegal immigration in the United States. For example, most immigrants in the country earn more money than they would if they had similar jobs back at home. Due to the strong American economy, most employers offer their employees good wages that other countries cannot match. Therefore, many foreigners keep looking for ways to make an entry into the countrys labor market (Haines 69). A study conducted among Mexican immigrants in the United States showed that even with all the expenses incurred living in a foreign country, their revenue in a year was three times that of their counterparts back home (Borjas 149).

The slow rate of economic growth in most countries is attributable to weak economic policies that do not offer the right solutions for dealing with the increasing demand for better income and higher living standards. Some of the factors that enable employers in the United States to hire illegal immigrants include changes in the global economic structures, lack of policies to control illegal economic migration, as well as weak labor policies (Heron 66). Changes in the global economic structures have made it easy for foreign investors to have operations in the United States. This means that low-skilled workers have a higher chance of getting well-paying jobs in the United States compared to their native countries. The concept of global migration of labor has influenced many people to move across the world in search for better jobs.

The nature of the immigration system in the United States is also a major cause of the increasing size of the illegal immigrant population. The system exists based on three pillars, namely promoting family reunion, meeting labor demands, and protecting Native Americans from the competition brought by foreigners (Berry 223). According to international relations experts, the American immigration system has channels for legal migration that many foreigners exploit in order to get a chance at experiencing the American dream. The biggest available channel is the one that allows employers to hire low-skilled workers through temporary visas in order to meet the demand in the labor market. Most of the foreigners who gain entry into the United States through this channel often refuse to go back home after the expiry of their visas (Berry 231).

Most of them are apprehended by federal agents and often deported, while others remain in the country illegally. Another immigration channel that many foreigners often exploit in order to gain entry into the United States is the 675,000 ceiling that the federal government has set on the number of permanent visas that can be given in a year (Berry 235). Many people get into the country in the capacity of being spouses, children, and parents of foreigners with permanent residence because they are not included in the aforementioned limit. This element of the system means that several people that cannot gain entry into the country through legal means, thus the option of using illegal avenues to cross the border (Haines 108). In most cases, people who get temporary work related visas choose to extend their stay in the country after their expiry dates because they know getting another opportunity is difficult and cannot stand a chance of loosing a well-paying job (Heron 73). Although it is illegal for any employer to hire an employee who is in the country unlawfully, the trend keeps growing owing to the fact that it is extremely difficult to verify the authenticity of documents.

One of the decisions that have played a major role in illegal immigration in the United States is the cancellation of the Bracero program, which allowed Mexican citizens special visas to work in American farms during the harvesting season (Laham 153). The program lasted for 22 years from 1942-1964, a period in which the United States benefited a lot from the input of Mexicans who replaced American citizens that had joined the army during the World War II. Although the program provided legal permits to qualified Mexicans, a great number of them that had failed to meet the qualification grade moved to the United States illegally in search for employment (Laham 155). Following the termination of the program in 1964, many Mexicans working in the United States chose to remain in the country illegally. International relations experts argue that the main reason as to why the Mexican workers were not willing to go back home at the time was the fact that they were not offered any monetary incentive to substitute the income they were getting (Laham 157). This phenomenon explains why the biggest percentage of the illegal immigrant population in the United States constitutes of Mexicans.

Another cause of illegal immigration in the United States is the network effect that develops out of the family reunification pillar of the immigration system. This effect is common among Mexican immigrants who have been in the country for several decades. Most people in Mexico keep making efforts to reunite with members of their extended family living in the United States (Borjas 236). Since most of them cannot get visas, they choose to use illegal means to be in the country. There more the illegal immigrants keep settling in the country, the larger the community gets over time. These communities slowly act as bait to the people in their native land to move to the United States and become part of the growing family in a foreign country (Heron 107).

The development of the network effect is attributable to several factors that have also influenced the growing number of illegal immigrants in the United States. These factors include the low cost of communication, transportation, and information services between the United States and Mexico (Haines 118). These factors have played a major role in the high number of Mexicans living illegally in America because the cost of crossing the border is far much less compared to foreigners coming from Asia, Europe, and Africa. Most Mexicans unsuccessfully attempt to cross the border several times before managing to get to the United States because a singe effort does not cost much (Borjas 251).

Impacts of illegal immigration in the United States

According to federal reports on illegal immigration in the United States, it is very clear that the phenomenon has had huge impacts on numerous elements of the American culture. The mushrooming size of illegal immigrant population has affected the countrys economy, health delivery system, the environment, as well as the security parameters (Berry 330). One of the economic impacts is that illegal immigrants have led to a breakdown in the wage structure due to the entry of low-skilled labor (Lee 8). Many American employers prefer hiring the illegal immigrants because their labor is cheap and would not complain even if when subjected to exploitation (Arnold 500).

This has led to a decline in the minimum wage offered to employees working in certain sectors. The counter effect of this change is the widening gap between the rich and the poor owing to the fact that there is an uneven distribution of wages and employment opportunities for legal American citizens greatly reduce (Lee 10). Another economic impact of illegal immigration is increase in housing prices, as residential real estate developers have acquired a culture of exploiting the growing communities of illegal immigrants (Arnold 519). A study on the state of the countrys real estate industry established that the prices of houses are very high in regions with a huge number of illegal immigrants (Berry 312). This means that legal American citizens living in those regions tend to suffer a lot because the housing prices in other regions remain within normal rates.

Taxation and provision of social services are important elements of the American economy. According to federal reports, illegal immigrants receive a lot of money through social services although they do not contribute a lot through taxation (Haines 211). This has in turn affected the effectiveness of federal, state, and local budgets because there are very many people supported in various ways without making any notable contribution (Lee 14). However, the availability of illegal immigrants has attracted the attention of financial institutions through mortgages as they sought to grow their revenue from the unexploited resource. This discovery led to numerous changes in the banking industry characterized by criticisms of financial institutions for encouraging illegal immigration through lucrative incentives. Many critics argue that the trend of giving mortgages to illegal immigrants exposes the countrys economy to great danger because unsustainable lending practices were inevitable (Lee 19). However, many banks exuded confidence in their decision citing it as a one of the avenues for economic growth because the poor implementation of immigration laws meant that their clients would not be easily deported. Financial analysts argue that this trend, which started a few years after the turn of the century, was one of the factors that led to busting of the housing bubble that had a huge influence on the global financial crisis (Arnold 535).

Illegal immigration in the United States has also led to the federal government incurring many expenses in law enforcement efforts. For example, the process of apprehending and deporting illegal immigrants uses many resources, which put a lot of financial strain on the government. The apprehended foreigners often have to be detained at a cost of $ 90 per person everyday before they are deported from the country (Lee 25). This is a huge expense that the government incurs every year in its efforts to protect the sovereignty of its people. Due to the dynamic nature of strategies applied by foreigners entering and staying in the United States illegally, the boarder control agents have employed the latest technology in monitoring the countrys boarders (Haines 238). The DHS reports that the number of people apprehended trying to cross the boarder illegally has tripled from the time the technology was installed.

The health care delivery system is another element that suffers a lot due to illegal immigration in the United States. Federal reports indicate that the high number of illegal immigrants have reduced the quality of emergency preparedness and the public health management systems. The DHS argues that their efforts with regard to developing emergency systems have become fruitless because they cannot establish the exact population in certain areas owing to the high number of illegal immigrants (Lee 27). The same case applies when delivering public health services in areas where the exact number of people in need of assistance is hard to determine. Lack of documentation showing the demographic composition of a region affects the effectiveness of delivery plans (Haines 300). Public health delivery systems cannot work without enough funding and workforce, all of which are provided depending on the exact number of people being served. The effectiveness of the health care delivery system is further heightened by lack of good communication between health care workers and illegal immigrant who do not understand any other language apart from their native one (Arnold 601).

Illegal immigration also influences a lot on the state of security in the United States. According to the DHS, there are a significant number of illegal immigrants involved in various forms of crime across various regions in the country. A study conducted on the security status in the state of California established that 17% of inmates were illegal immigrants who were waiting to be deported as soon as they finished serving their jail term (Haines 356). Although most illegal immigrants act keenly in order to avoid any form of interaction with law enforcement agents, lack of employment pushes them to commit petty crimes for survival. Interestingly, regions with a high number of illegal immigrants have fewer cases of violent crime. Studies that have been conducted with regard to the relationship between immigration and crime rates in the United States have contradicting results that make it hard to make a reliable conclusion. However, the DHS reports that cases of violent crimes involving illegal immigrants are very common in border counties (Haines 359).

These cases mainly involve smuggling of goods and human trafficking. Once those involved in these forms of crime manage to settle in the country, they continue with their criminal activities. For example, in 2009 the federal government released a report on the state of crime in los angels and identified a number of illegal immigrants that were members of the 18^th street gang. According to the report, 80% of the gang members who had a questionable immigrant status were identified as natives of Mexico and Central America (Arnold 631). The main criminal activities of the gang were drug trafficking, carjacking, extortion, and homicide. In addition, the gang was also associated with the numerous cases of robbery, identification fraud, and drive-by shooting cases reported in the city (Arnold 636). Illegal immigrants are also involved in cases of terrorism, which ranks as one of the major threats to the security of the United States.

The federal government has also noted environmental degradation as one of the major impacts of illegal immigration, especially in its border with Mexico. The degradation often develops from the high number of abandoned cars in the lands along the border (Roberts 6). In addition, the high numbers of illegal immigrants that walk trough the lands as they enter the country leave a lot of litter behind, which eventually lacks someone to collect. Reports by the immigration department also state that the illegal immigrants are responsible for the numerous wild fires reported on various American borders as they use them to distract the movements of immigration agents watching the borders. These fires destroy thousands of acres land that also cost a lot in taxpayers money with regard to damage control (Lee 30). Other reports indicate some illegal immigrants die or suffer serious injuries during their attempts to cross the American border (Roberts 13). This normally happens when the foreigners try gaining entry into the country through dangerous zones that have wild animals or have do not have somewhere one can seek help.

Policies for addressing illegal immigration in the United States

Since the first cases of illegal immigrants were reported in the United States, the federal government has come up with a number of legislation geared towards stopping its development. According to the countrys immigration laws, any illegal immigrant apprehended is liable to a fine, jail term or both. It is illegal for anyone living in the United States to dodge inspections carried out by immigration agents, as well as providing false information in order to gain entry and remain in the country (Berry 470). These offenses attract a maximum jail term of two years depending on the degree of violation. The federal government has developed a number of policies geared towards preventing illegal immigration. One of the policies on employment stipulates that illegal immigrants in the United States are not viable to receive privileges such as getting a professional license to work (DeLaet 80).

However, due to the numerous efforts human rights groups, states such as California have made amendments to the policy in a bid to reduce crimes related to work permits. During the tenure of President George W. Bush, the federal government created a policy that would require employers to submit information about their employees for auditing in a bid to uncover illegal immigrants (DeLaet 85). This policy has been very effective under the current government led by President Barrack Obama, who has often reiterated the need to clean up the mess that is denting the countrys immigration system. Illegal immigrants uncovered through the audit process often face deportation as soon as their immigration status is confirmed.

Over the years, the federal government has made numerous efforts to increase the security and patrol activities in its borders in a bid to apprehend foreigners gaining entry into the country through places that are not designated as immigration points (Berry 486). One of the plans has been fencing the countrys border with Mexico, which has been a major entry point for many illegal immigrants in the country. The federal government has invested many resources in securing the countrys borders by employing thousands of patrol agents (DeLaet 89). However, the fence that covers a third of the 2000 miles long border has slowly been turned into a political issue and a source of attack from human rights groups (Arnold 700). The current administration has had to deal with numerous challenges while addressing this problem owing to the intense pressure coming from various human rights groups. They argue that the government should propose a new strategy for dealing with them because in reality they make a huge contribution to the growth of the economy (Haines 501). However, the countrys strict policy on threats to national security such as terrorism has left the government with no choice other than employing tough measures to stop illegal immigration.

One of the legislation that has helped in addressing this problem is the U.S. Patriot Act of 2001. This legislation came following the September 11 terror attack that alerted the federal government on the huge threat posed by laxity that was going on within immigration department (DeLaet 100). This act gave federal agents and the DHS to apprehend and deport any illegal immigrants suspected of involved in terrorist activities. In addition, any illegal immigrant found to have any form of association with a group or organization marked as a threat to the countrys security should be deported immediately. Over the last couple of years, the Obama administration has faced a lot of criticism from human rights groups with regard to the implementation of this legislation, which they feel has greatly violated the rights of the apprehended people. The act provides that an apprehended illegal immigrant should not be given a hearing, but otherwise deported immediately. The federal government argues that it cannot take chances on the safety of its people by showing mercy on criminals.

Terrorism has been a major issue with regard to homeland security, and reports indicate that illegal immigrants in the country have often been easy targets for terrorists seeking people to help them in their missions (Roberts 20). In some cases, the apprehended individuals are tried for being in the country illegally before being deported. However, the process of deportation has its own complications that have made the process of reducing the illegal immigrant population less effective. One of the challenges is importing children who are American citizens by birthright yet their parents are illegal immigrants (Roberts 27). Many human rights groups have used this issue as the basis for attacking the federal government over it policy on illegal immigration. They argue that deporting an illegal immigrant parent yet their children are legal American citizens is a violation of the constitutional rights of the minors. However, the government has refused to change its position as provided for in the deportation laws of 1996 (DeLaet 109). The only change that has happened under the leadership of President Obama is a reduction in the number of deportations, owing to the introduction of a system categorizing illegal immigrants into priority groups based on their possible threat to the countrys security.

Another legislation that has formed the basis for illegal immigration policies in the United States is DREAM Act that has failed to pass since its introduction to the senate in 2001 (DeLaet 129). This legislation focuses on the development and education needs of alien minors. According to the provisions in the act, illegal immigrants that have minors born in the country can get temporary residency that involves a number of conditions that have to be met before receiving permanent residency (Arnold 778). Its proponents argue that it would be a good strategy for reducing the number of illegal immigrants because they would be registered, thus making it easy for the government to track their movements. However, the administration of President Obama has enacted a few provisions from the act in a bid to regulate the cost incurred by the federal government while addressing the problem. For example, eligibility for Deferred Action for Childhood Arrivals (DACA) requires the applicants to prove that they started living in the country before turning sixteen years, have enrolled in high school or completed, acquired a GED certificate, as well as their innocence with regard to conviction for any offence (Roberts 44).

Conclusion

The United States of America is one of the most desirable countries to live in owing to its stable economy, good political environment, education system, and good record in promotion of human rights. There are several conclusions with regard to the issue of illegal immigration in the United States. First, the challenge of illegal immigrants in the country is a reality that the federal government needs to address with the utmost priority. The mushrooming size of the illegal immigrant population is a huge source of threats to homeland security. Owing to the fact th

Wellbore stability definition

Wellbore stability refers to sustainability of the borehole from falling or breaking down and is achieved through use of drilling fluid programs, casing programs and efficiencies of drilling operating procedures (Simangunson et al, 2006). Wellbore stability is achieved through identification; adoption and implementation of best practices (cf. Yongfeng et al, 2009). Sustainability of wellbore stability is influenced by appropriateness of data while drilling operations are in progress. Effectiveness of wellbore stability and predictions depends on physical properties of the rock, present stresses and pore pressures and variability of the drill model prediction (Gisolf et al, 2009).

The wellbore stability is influenced by controllable factors and natural factors (uncontrollable factors).

The engineering controllable factors that influence wellbore stability

• The mud density and prevalent bottom hole pressure
• Inclination and Azimuth of the well
• Transient pore pressures
• Chemical properties of the rock and subsequent rock-fluid interaction
• Physical properties of the rock and subsequent rock-fluid interaction
• Vibration level of the drill string
• Thermal temperatures
• Absence or presence of erosion

The engineering natural factors that influence wellbore stability

• Incidents of Faults formations
• Incidents of Natural fratures on rock
• Incidents of increased Stresses especially high-in-situ
• Incidents of increased Stressed formations for instance tectonic
• Prevalence of Formations that are unconsolidated
• Prevalence of induced over-pressured shale collapse
• Prevalence of naturally over-pressured shale collapse
• Possible prevalence of mobile formations

Mechanism of achieving wellbore stability

Wellbore stability (Weinheber et al, 2010) could be achieved through conducting finite element analysis. Finite element analysis via FLAC makes it possible to determine factors that affect depth that a fluid penetrates. The depth that a fluid penetrates is important considerable factor when carrying out horizontal drilling (cf. Cantaloube et al, 2010). Finite element analysis makes it possible to determine wellbore stability when simulated production is in progress.

Wellbore stability could be achieved by controlling coal fine content (Kristiansen, 2004) that is generated when drill bit action carries drilling fluid into cleat system. This results into plugging of the permeability pathways and contributes into formation damage.

In the event wellbore develops instability subject to pressure drawdown (Estep et al, 2010), a perforated or slotted production liner could be used. The depth of fluid penetration should be maintained at 2.2 metres (cf. Chen et al, 1998). The 2.2 metres is recommended if there are no opportunities for filter cake formation (Weinheber et al, 2010). Finite element analysis via SLAC has demonstrated a small diameter for instance 5 centimetres has a higher preference subject to its contribution in wellbore stability.

Wellbore stability (Hawkes & McLellan, 1997) that is negatively influenced by lost circulation and differential sticking should be achieved through pulling of the drill pipes. This provides opportunity for running casing. There should be management of annulus and frictional pressure losses that influence of effective circulating density (ECD). Management of ECD (Zhang et al, 2006) results into management of possible lost circulation. As a result, lower mud weights are recommended since they make it possible to achieve required bottom hole pressure that contributes into sustainability of the wellbore stability.

Advantages of wellbore stability

• Decreased damage to formation due to low reactivity of the water
• Minimization of clay sweeling and wellbore stability problems
• Stabilization of temperatures
• Reduction of waste production
• Improved rate of penetration and efficiencies of circulation
• Increased lubrication that decreases chances for friction
• Prevention of hydrate formation

Disadvantages of wellbore stability

• It increases costs
• Increases time

Wellbore instability

Wellbore instability (Nguyen et al, 2007) is defined in terms of nature or mechanism the rocks respond to natural or induced overpressures about the wellbore when drilling operations are in progress. The response of a wellbore depends on concentration of stress. Wellbore instability (Chen et al, 1998) differs based on formation damage and level of interaction of the drilling fluid. Thus, wellbore instability is influenced by interplay of mechanical factors, chemical, hydraulic and thermal factors (cf. Hawkes & McLellan, 1997).

Management of wellbore instability ought to consider a rock as a continuous material which means; failures that occur in a wellbore and affect wellbore stability should be taken as single initial failure point. While consideration for single initial failure point ought to be put into account (Maury & Sauzay, 1987), the rock ought to be considered as a discontinuous material and is subjected to stress. This means, instability of a wellbore arises due to single point failure (Hawkes & McLellan, 1997).

Despite influence of single point failure as contributor to wellbore instability, the wellbore should be capable of accommodating casing controls (Gaurina-Medimurec, 1994) and possible installation of a downhole apparatus. This is in the event of considering possibilities of noncircular and irregular layout of the rock subject to discontinuity or continuity of the materials. Wellbore instability (Maury & Sauzay, 1987) is managed well through grain scale Discrete Element Modeling (DEM).

DEM takes into account the discontinuity or continuity of the rock material. DEM is achieved through rock modeling as a function of grains that are bound by cement like content and there exists pore spaces between the grains (Gauriona-Medimurec, 1994). This implies any possibilities of a micro crack of the rock because of influence of tensile failure or shear failure is attributed to concentration of stress.

Causes of wellbore instability

Wellbore instability (Nguyen et al, 2007) is classified on the basis of mechanical or chemical properties. The mechanical factors (Gaurina-Medimurec, 1994) that predispose wellbore instability include mechanical failure of the rock which occurs around the wellbore (Yongfeng et al, 2009), high mechanical natural (Chen et al, 1998) or induced stress (Gaurina-Medimurec, 1994), low tensile strength of the rock (Hawkes & McLellan, 1997) or low shear strength of the rock (Chen et al, 1998) and implementation of inappropriate drilling practices (Nguyen et al, 2007) that impact negatively on the wellbore stability.

The chemical causes of wellbore instability are brought about by chemical interaction (Nguyen et al, 2007) of the drilling fluid and the rock subject to presence of minerals that are water soluble. Mechanical and chemical wellbore instabilities contribute into drilling complications that make the process unsustainable in terms of costs incurred in managing wellbore instability predisposing factors (Zhang et al, 2006). This implies analysis of wellbore stability during planning phase should account for economies of scale brought about by wellbore instability.

Wellbore instability (Nguyen et al, 2007) results from inaccurate determination of pore pressures. These inaccuracies are made when carrying out wellbore stability analysis and contribute into costs incurred through stuck pipes, lost wellbore, damaged formations, increased costs of drilling operations and increased incidents of wellbore lost circulation.

The major contributors for wellbore instability that are secondary to mechanical and chemical causes include washing, reaming and overpull (Nguyen et al, 2007), vulnerability of bottom hole assembly to sticking (Gaurina-Medimurec, 1994), losses of the drilling fluids (Chen et al, 1998), and failure of the casing reaching the bottom (Maury & Sauzay, 1987). The wellbore instability has been managed through drilling of a sidetrack. There is therefore need for improving geomechanical models and optimization of drilling practices in order to reduce chances of wellbore instability.

The indirect indicator for prevalence of wellbore instability

• Prevalence of friction that contributes into high torque and drag forces
• Rising incidents of circulating pressures
• Possibilities of hanging up of drill strings casing or coiled tubing
• Possibilities of rise in circulating pressures
• Incidents of stuck pipes
• Incidents of increasing drillstring vibrations
• Possibilities of drill string failure
• Incidents of control problems
• Incidents of incapabability to control and run logs
• Incidents of inappropriate logging responses
• Incidents of leakage of gases subject to poor cementing procedures
• Vulnerability of keyhole seating
• Incidents characterized by rising doglegs

The direct indicators of wellbore instability

• Poor calibration leading to oversized hole
• Poor calibration leading into undergauge hole
• Vulnerability to excess volume of cuttings
• Vulnerability to excess volume of cavings
• Possibilities of cavings at the surface
• Possibilities of hole fall post tripping
• Utilization of excess cement

Problems with wellbore stability

Problems that affect wellbore stability are based arise during initial planning phase (Wolfe et al, 2009). The planning phase fails to provide a stable design that accounts for possibilities of casing and fluid plan, nature of trajectories and challenges that affect the trajectory. This implies, unmanaged geomechanical problems that could affect the stability of the design contribute into wellbore instability. This predisposes the wellbore to collapse, lost circulation, stuck pipes and possibilities of casing collapse (Cantaloube et al, 2010).

It also provided environment for damage of the reservoir and inability to achieve required logging data which makes wellbore real time stability forecasts difficult and undependable. Some challenges that affect drilling as a function of wellbore stability problems include vulnerability to deviated wellbore, near salt, stress based areas (Simangunson et al, 2006). The stratums in tectonic zones pose problems of wellbore instability. Possibilities of intersection of weak bedding planes and unfavorable angles present problems to wellbore stability since they have capacity to provide opportunities for mud and fluid infiltration that finally contribute into collapse (Tan et al, 2004).

Methods for recovering wellbore stability

Wellbore stability could be recovered by recovering lost circulation material (Estep et al, 2010). This is based on a method for recovering lost circulation materials that involves directing fluid into the drill. The material should have sufficient magnetic property than the material being recovered (Zhang et al, 2006). This should be followed by magnetic separation of the materials based on strength of magnetism. The materials that cannot be recovered through use of magnetic separation should be separated through centrifuging or solution process. This utilized the property of different solubility properties of the materials. The materials that cannot be recovered should be disposed off safely (Tan et al, 2004).

Methods for managing the materials that cannot be recovered

The materials are disposed offshore or discharged overboard from the drilling vessel, a process that is termed as offshore discharge (Chen et al, 1998). The materials are treated by using solid control equipments. This occurs if the materials have no negative impacts on the aquatic life (Gaurina-Medimurec, 1994). The materials could be disposed off through offshore reinjection by being ground into fine materials before they are disposed. The materials could also be onshore disposed. In onshore treatment, the materials undergo thermal desoption or are used for land filling and land spreading.

Maintaining wellbore stability

Maintenance of wellbore stability is important process in drilling operations. Maintenance of wellbore stability has been based on failure studies on wellbore stability (Tan et al, 2004). Maintenance is achieved through use of managed pressure drilling. This involves use of surface pressure. Downhole problems should be reduced by appropriate casing control measures (Zhang et al, 2006). This involves casing while drilling method.

In presence of high tectonic stresses, wellbore stability should be maintained by decreasing opportunities that could result into collapse of the wellbore subject to interferences of over pressured shale. There should be balance between hydrostatic pressure and fracture pressure (Cantaloube et al, 2010). Adequate casing off of the formation damages should be done. This should be coupled with use of sufficient drilling fluid.

Preventing wellbore instability

Prevention of wellbore instability is important step in drilling operations. The approach for managing wellbore instability affects sustainability of drilling operations like cement zonal isolations (Hawkes & McLellan, 1997). Wellbore instability increases costs and affects completion. Wellbore instability should be prevented by wellbore stability forecasts through use of wellbore real time stability analysis. There should be ongoing wellbore measurements in order to determine mechanism through which drilling operations affect wellbore (Nguyen et al, 2007). Drilling operations impact on LWD measurements hence need to use real time images and drilling data in order to ensure remedial strategies for risk management are implemented timely.

Differences between onshore and offshore wellbore stability and instability

Onshore drilling is affected more by wellbore stability than offshore drilling (Nguyen et al, 2007). This means, approaches towards management of wellbore stability should be concentrated on onshore drilling than offshore. Improved approaches for management of wellbore stability in onshore drilling could result into decrease of costs in terms of well construction and production operations. This is due to higher temperatures and unconsolidated sand. Onshore drilling is affected more by presence of deposits of gas hydrates and pore structure fractures that impact negatively on the wellbore stability (Chen et al, 1998).

In onshore, possibilities of increased wellbore stresses are much higher than in offshore which impacts on wellbore stability. The problems of lost circulation are more pronounced in onshore than in offshore. As a result, incidents of stuck pipes and wellbore collapse are much evident in onshore than in offshore. Due to incidents of wellbore stability and instability in onshore drilling, it is important to carry out wellbore stability modeling (Hawkes & McLellan, 1997).

Wellbore stability modeling facilitates in wellbore design by helping to determine wellbore trajectory. The process results into identification of hazards that could be incurred. This helps in risk analysis and mitigation. The wellbore stability real time forecasts are therefore important in onshore drilling and operations. Real time forecasts help in determining possibilities of breakout areas and possibilities of drill induced fractures (Maury & Sauzy, 1987). This means, adoption of wellbore real time stability forecasts plays an important role in geomechanical analysis of rock materials on basis of discontinuity or continuity hence positively impacting on the success for the drilling operation.

In onshore drilling, geomechanical responses are influenced by variation in depressurization induced gases that are produced from deposits of onshore hydrates. As a result, a reservoir wide pressure decline occurs (Nguyen et al, 2007). Due to variation in pressures, differences emerge between vertical and horizontal wellbore. In offshore, reservoir depressurization results into anisotrophic stress that contributes into shear failures. This results into decrease in the loads casing as observed in vertical wellbore. The management of the failures requires management of perforation. The problems in onshore arise due to rise of compression on the upper segments of wellbore casing. As a result, there occurs local shear failure and local shear yielding which affects bonding between grains (Yongfeng et al, 2009). The outcomes are characterized by formation of cavities within the perforations. The stability could be maintained by managing localized shear failures.

Significance of Wellbore stability forecasts

Wellbore stability forecasts are important in drilling operations because they facilitate in determination of drilling related failures (Wolfe et al, 2009). The common drilling failures arise from unstable boreholes subject to possibilities of lost circulation, stuck pipes and lack of casing control. Wellbore stability forecasts makes it possible to determine behavior of wellbore stability and utilize the knowledge that is acquired post forecasts to carry out modeling in real time (Estep et al, 2010).

Wellbore stability forecasts helps in providing real time wellbore instability incidents and their prevalence rates. It facilitates in determining mode of failure hence institute appropriate mitigation approach timely. This helps to minimize costs and pave way for time management. Wellbore stability forecasts provide opportunity for designing and development of stable trajectories and determination of mud weights hence identification of optimal equivalent circulating density (Zhang et al, 2006).

Wellbore stability forecasts and wellbore real time stability makes it possible to gain knowledge on prediction of pore pressure and management of failure modes, provides opportunity for planning and trajectory optimization as well as prediction of reservoir compaction (Cantaloube et al, 2010). The primary function of wellbore stability forecasts is to determine reservoir stimulation designs in onshore drilling, determine appropriate perforation design that could be implemented and provide necessary information on earth stress analysis. It also makes it possible to determine selection of mud weights hence facilitate in wellbore cleaning designs that could be effectively be implemented.

Advantages of conducting wellbore stability forecasts

• To decrease opportunities for non-drilling time
• To decrease opportunities for casing strings
• To decrease production time by optimizing on operational time and production resources
• To facilitate selection of the mud
• To make it possible to implement appropriate wellbore cleaning design

Wellbore real time stability

Wellbore real time stability is a function of real time updates that is realized through the use of geomechanical modeling outputs (Zhang et al, 2006). The model outputs are generated based on actual geomechanical conditions as drilling operations progresses. Wellbore real time stability is fundamental in providing real time updates within a timeframe that could create environment for proactive decision making as operations processes progresses (Simangunson et al, 2006). Wellbore real time stability contributes into close to real time monitoring of drilling operations as well as providing foundation for wellbore stability modeling.

Wellbore real time stability forecasts provide opportunity for remote monitoring of drilling operations. Thus, modeling and wellbore risk management strategies are appropriately allocated (Kristiansen, 2004). This helps in improving drilling performance and safety assurance. Wellbore real time stability analysis provides real time streaming data that facilitates conceptualization of stability incidences.

It provides opportunity for conducting sanding studies and determination of completion design through identification of uncertainties through uncertainty analysis (Estep et al, 2010. Wellbore real time stability provides vital information that is important in carrying out kick analysis, reservoir studies, provision of drilling reports and provision of geophysical data with regard to sonic, density and seismic impacts.

Software used to model well to predict wellbore stability

A variety of software is used in wellbore modeling to predict wellbore stability. The software is used based on the needs for the wellbore stability. For instance, the Borehole Integrity Analysis System (BIAS) whose copyrights are owned and controlled by Bakers Atlas has capability to compute the quantity of wellbore breakout that could be achieved subject to variation of mud weights (Simangunson et al, 2006). BIAS makes it possible to select the right mud weight that conforms to determined size of breakout. Thus, BIAS make sit possible to use lower mud weight. BIAS makes it possible to stimulate drilling induced features.

Bias provided necessary information on stuck pipe of loose mud. Another software that could be used is a window based ERDesigner (Gisolf et al, 2009). The window based ERdesigner makes it possible to generate colored reports automatically, development of a preliminary well plan. The window based ERdesigner makes it possible to determine rig type and power requirements and provides analytical data that could be used for implementation of the drilling program. DRILLWORKSPREDICT PROFESSIONAL 2004TM software family could be used.

The DRILLWORKSPREDICT PROFESSIONAL 2004TM includes software like Drillworksproject, Drillworkspressbase, Drillworks3D, DrillWorksPREDICTTM and DrillWorksGeostress. For instance DRillworksAnaseis software is known for coreection of seismic bias and makes it possible to carry out seismic processing which is improntant element in geopressure analysis. The software makes it possible to conduct real time wellbore stability analysis (Estep et al, 2010). It makes it possible to identify and correct opportunities for shear failures, fracture and lost circulation.

Data needed to predict wellbore stability

Prediction of wellbore stability requires use of sonic data either in form of DTP or DTS (Estep et al, 2010). The density related data and shale indicators are communicated. The process of data communication is carried out in real time. The rock mechanical analysis, assessment and evaluation are carried out on site through a LWD system that is installed on site (Cantaloube et al, 2010). In absence of an on site LWD system, the data could be communicated over the internet to the office for further analysis. LWD caliper measurements are done, based on logging toll and wellbore wall. Maximum and minimum axes of ellipse could be computed in order to determine orientation of the axes. The outcomes are a three dimensional wellbore caliper images. These are created after logging.

Use of high resistivity images (Simangunson et al, 2006) that are either two or three dimensional make sit possible to determine orientation of fractures. The information makes it possible to optimize on wellbore direction that could contribute into higher production. Other data elements that are important include fracture frequency, fracture size and fracture location (Zhang et al, 2006). The three elements of fracture contribute in design, remedial plan development and analysis of a reservoir and its corresponding future engineering processes. Angles of trajectory are also determined.

The failure modes and economic significance

The common failure modes that impact on wellbore stability are brought about by incidents of tensile failure (Wolfe et al, 2009), shear failure or possibilities of matrix or collapse of the pore (Zhang et al, 2006). The common indicators of preeminent failure modes include vulnerability to hydraulic fractures that may be natural or synthetic. It could also be elevated by possibilities of local mobilization of existing faults.

Failure modes could be stimulated by incidents of spalling that arise subject to incidents associated with swabbing and tripping (Wolfe et al, 2009). Failure modes in onshore drilling could be brought about by effects of drag force. Drag force has capability to contribute into increasing sand production. Failure modes have also been identified to develop from ductile formations that arise from subsalt or salt, their corresponding evaporates. Possibilities of soft shales could result into squeeze that could result into restriction of the wellbore. Incidents of swelling have higher capability of contributing into failure modes (Kristiansen, 2004).

The stability of the shale

The stability of the shale is affected by interaction of one or more several factors for instance period of exposure (Simangunson et al, 2006), the degree of filtrate chemistry applicable or degree of solution process (Tan et al, 2004), the rate of ionic transport and feasibility of dehydration. The chemical property of the shale could result into chemical instability. The outcome is characterized by impact on the mud weight and possibilities of water influx (Weinheber et al, 2010).

Influx of water as ionic component could contribute elevates instability. Water infiltration contributes into increase of wellbore pore pressure that in turn results into decrease of the strength of the shale. The outcome manifests itself due to existence of a potential gradient between the wellbore pressure and the shale pore fluid pressure (Nguyen et al, 2007). It could also result from possibilities of chemical potential difference which contributes into local gradient between the drilling and the shale pore fluids.

The smectitic shales

Smectitic shales are characterized by increasing ductility and creepiness (Yongfeng et al, 2009). Smectitic shales contribute are associated with features like decreased wellbore pressures. The wellbore pressure impacts negatively on stability through acceleration of the creepiness (Maury & Sauzay, 1987). The smectitic shales result subject to sensitivity of the mud filtrate ionic strengths that is subject to chemical properties. However opportunities for inhibition could result following sweeling and slouging of the shale (Chen et al, 1998). Smectitic shales are managed through use of salt, gilsonite and synthetic polymers that have capability to increase stability by decreasing ductility which tends to translate smectitic shales into illitic shales.

The significance of illitic shales

Illitic shales are characterized by higher concentration of quartz (Zhang et al, 2006). This makes illitic shales to demonstrate higher stability compared to smectitic shales. Due to decreased ductility property, the illitic shales exhibit brittleness and hence inert (Kristiansen, 2004). The failures that are associated with illitic shales are brought about by increased pressure drawdown. This is subject to brittleness and energy that has been stored between the pore fluids.

Costs of damage and solutions

Wellbore construction costs fall into three categories namely the lost circulation costs, stuck pipes and flat time that are encountered during casing points (Wolfe et al, 2009). Delay in responding to wellbore instability creates environment for increase of the costs due to changes in geopressures and geo-stresses. The costs with regard to wellbore stability should be determined at wellbore planning phase, wellbore real time stability forecasts as the drilling operations are ongoing and during post drilling analysis.

The costs of the damages are caused by lack of wellbore real time stability forecasts (Zhange et al, 2006). Wellbore real time stability forecast helps to identify failure criteria models hence contributing into improvement of drilling methods or proposal for implementation of improved drilling method operations. Wellbore real time stability forecasts helps to determine strength of the existing rock hence designing of improved methods of improving wellbore stability and managing wellbore instability.

The management of costs of damage should be based on impact of time and fluid chemistry of the rock material which would contribute into understanding of wellbore stability and instability (Kristiansen, 2004). The cost of damage should be a function of relationship between analytical and finite element modeling. The methods that should be implemented should be based on feasibility towards management of wellbore stability and instability subject to application or remodeling of existing models for prediction of wellbore stability (Wolfe et al, 2009).

Analysis should provide balance between impacts of temperature and interaction of streamlined workflow based on utility of stochastic modeling. The outcome of temperature and streamlined workflow should be evaluated against correlation data on the strength of the rock material. Use of stochastic modeling should be based on designing and constructing a predictive model.

Sustainability of wellbore stability

Sustainability of strategies for managing wellbore stability and wellbore instability lies in capacity to development of software that can provide close to real time pore pressure and prediction of fracture gradient (Estep et al, 2010). This would result into implementation of real time drilling productions and processes. There is need for improvement of methodologies for managing wellbore stability and instability at onshore and offshore operations. There is need for research and development on prediction of subsalt pore pressure (Weinheber et al, 2010). This should be achieved through the use of three dimensional earth modeling.

The oil and gas drilling industries should focus on maintenance of wellbore integrity. The requirement for integrity should be achieved through efforts and investment in research in order to attain casing reduction and decreased mud related expenses (Cantaloube et al, 2010). This should be based on contingency casing designs. This means identification and adoption of best practices should form core foundation for improving wellbore stability prediction and real time forecasts.

References

Cantaloube, F., Spickett, R., Yekta, K. and M. Anderson, (2010) Optimization of stimulation treatments in naturally fractured carb

Abstract

The September 11 attacks in the US brought mixed fortunes to the safety of the aviation industry because over the years, the world has witnessed increased aggression by terrorists and other criminals in launching airport attacks. Even though terrorism is a big threat to the safety of commercial airports, the scope of this paper transcends terrorist threats to include other aspects of safety in the operation of commercial airports. Some of these aspects include the building of residential and commercial buildings (in and around airports), runway incursions, runway excursions and bird strikes (among other natural disasters that may pose a risk to the safety of commercial airports). These are the existent security threats identified in most commercial airports around the world. Based on these security threats, this paper questions the usefulness of traditional safety considerations for commercial airports. Instead, this paper proposes new methods of improving the safety of commercial airports by recognizing the diversity of airport threats and the need for integrating human inputs into safety management systems. However, this paper recognizes the need to maintain traditional security measures but it also challenges the relevant authorities to improve such systems by incorporating new security measures that can deter present-day criminals. The realization of improved safety in our airports therefore warrants a renewed focus on how we perceive airport security threats.

Introduction

Flying is the safest mode of transport (Gladwell 2001, p. 53). This statement characterizes the airline safety perception among most travelers. From, this statement, undoubtedly, the level of safety in the transport industry is a crucial factor to consider while making the decision to determine which mode of transport to use. Though there is a common perception among many observers that airline transport is the safest form of transport, few people know the extremes that airline personnel have to undergo to ensure the industry remains safe (Wiener 1988, p. 433). However, many people are involved in ensuring that airline transport is safe. They include, flight engineers, pilots, airline manufacturing companies, commercial airline companies and air traffic organizations. These institutions are mandated to ensure the airline industry remains safe and newer methods of airline safety control are properly integrated into existing safety systems.

The commitment to ensure airline safety is normally evident in different aspects of airline traffic control including aircraft design, avionics, engine design, and system designs. However, airline safety is also extended to less-known aspects of safe operations such as airport designs, and dimensional standards (National Research Council 2007, p. 1). Safety is therefore an integral part of the operations in the airline sector and it may manifest in different forms, including standard operating procedures, adoption of new technology and ensuring that safety is the driving force behind airport operations (Parasuraman 1996, p. 91). The Airports Council International (ACI) believes that safety in the airline industry is not only defined by what the industry is but what is done (on a daily basis) to ensure air traffic safety (National Research Council 2007).

Since the aviation industry is a dynamic and multifaceted industry, many people ponder what airport security entails. Rome (2010) explains that, airport security refers to the security and techniques used to protect airports and aircrafts from crime (p. 73). Indeed, alongside seaports, railways and roads, airports witness large volumes of human traffic. Due to the sheer volumes of people within this transport terminus, airports remain a prime target for crimes such as terrorism. Furthermore, due to the high concentration of people within one aircraft, many terrorists perceive aircrafts to be a prime lethal weapon and target for their operations (Davies 1982). Indeed, the September 11 attack in the US is a prime example of how terrorists have targeted airports and aircrafts to launch their attacks. The world has witnessed other terrorist attacks such as the 1976 Cubana flight 455 which was shot down by terrorists (Marks 2010). This attack claimed 73 lives. Among other fatal attacks, which were caused by a lapse in airport security is the death of nearly 400 people which was realized after Air India (flight 182) was bombed by terrorists. The attack happened after airport officials failed to detect a bomb that was planted on the flight. The attack happened in 1985 (National Research Council 2007). The year 1994, also played host to another airport attack on Philippines Airlines (flight 434) that caused the death of one person after airport security detected the threat and foiled the attack before any more casualties were reported (National Research Council 2007). In 1972, three members of the Japanese Red Army launched an indiscriminate attack on civilians at an airport by firing at civilians and throwing grenades at innocent people (National Research Council 2007). The three assailants were later contained by airport officials (but after killing 24 people). Rome and Vienna airports also played host to similar attacks after unknown gunmen opened fire at innocent civilians on the airport terminus. The attack saw close to a dozen people dead (National Research Council 2007). In 2002, a similar attack was reported at a Los Angeles airport. The assault resulted in the death of two people (National Research Council 2007).

From the history of airport attacks, airport authorities have always been on high alert to avert any terrorist attacks. Such cautiousness has seen several airport attacks averted. For example, in 2006, British authorities detected a terrorist plot targeted at bombing aircrafts originating from the US and UK and averted the same (National Research Council 2007). This terrorist threat accounted for the first red alert in the US.

To many aviation authorities, airport security may amount to different things. However, to common people, airport security involves the provision of measures that protect people from grave harm. Across the globe, drug seizures and the trafficking of human beings has also been reported as a real threat to airport security (National Research Council 2007). In addition, the trafficking of illegal goods across airports is one such aspect of airport security that most people perceive to be important in airport security management. The perpetrators of such activities are often attracted to airports because of their accessibility to other countries. Airports are also targeted transit points for illegal goods such as ivory, and drugs. Smugglers are known to use airports for transmitting illegal goods across continents, thereby contravening international laws governing the same. These illegal goods may cause grave human harm if their trade is left to flourish. However, most importantly, if this trade is allowed to go on, it amounts to great airport security contravention. Aside from this fact, the biggest danger associated with illegal trade across airports is the fact that such illegal traders are often dangerous and they do not care about the wellbeing of other people (House of Commons 2010). Therefore, such criminals may pose a threat to the security of airport officials and by extension, the public.

Despite the surge in terrorist attacks and other forms of airports security violations, air traffic volumes are still set to increase in the coming decades. For instance, in the next two decades aircraft manufacturers estimate that air traffic is expected to grow by nearly 168% (House of Commons 2010). The growth in passenger numbers during the same period is estimated at 5%. Currently, the US department of homeland security estimates that about 730 million people use airport services every year and nearly the same number of people has their luggage checked for items that contravene airport security rules (annually) (House of Commons 2010). Airports are just a small part of the factors leading to an infringement of air traffic safety. For example, a recent survey by Burke (2008) shows that about 30% of all air traffic accidents involved an oversight of one aspect of airport safety. However, airports are complicated areas of operations because there are some factors in the airport environment, which may not necessarily be within the control of airport authorities. Such issues may include the weather, inadequate air safety guidance (and the likes). Therefore, many causal factors may cause a lapse in airport safety. Some researchers such as Burke (2008) estimate these causal factors to be more than 70 but the House of Commons (2010) groups these factors into seven categories including, lighting and marking, runways and taxiways issues, information issues, external hazards, apron and ramp issues, ATC operations and procedures issues, and aerodrome issues. The sheer size of airport related issues highlights the importance of all stakeholders in the maintenance of airport security to work together.

Nonetheless, the main problem associated with the understanding of airport security is the lack of proper data collection and data synchrony among different airports in the world. For example, there is poor quality of information regarding which airport security problems originate from ground operations and which ones originate from maintenance operations. Within the same sphere of understanding, Burke (2008) explains that, Within the accident information which is being collected, a general lack of attention to the organizational factors and corporate culture factors in data collection taxonomies is present which further impedes deeper insight (p. 45). The poor focus of organizational structures and corporate cultures (as impediments to understanding airport security) has however not been witnessed in all parts of the world. There are some statistics, which show the main causes of airport security lapses such as recent reports by the European accident investigations, which highlight the different lapses in safety system information among various airport safety institutions as another barrier to understanding airport security (Harris 2002, p. 1). For example, the 1995 Daventry accident and the 1991 Edinburgh accidents were mainly attributed to poor maintenance and poor handling of ground operations (Harris 2002, p. 1).

Understanding the importance of airport safety in todays multifunctional society is therefore gaining increased importance, especially with increased emphasis on non-traditional concerns such as environmental factors. For instance, there is reduced public tolerance to environmental effects of airport activities and third party casualties associated with poor air traffic controls (Harris 2002, p. 1). These new and emerging trends are further piling up more pressure to airport authority officials to maintain high safety standards through integrating new technology and coming up with innovative ways of tackling airport security issues (Rasmussen 1986). However, airport authorities are still expected to meet the growing capacity issues and environmental concerns associated with air traffic operations. From this growing complexity of operations, there is increased attention to the fact that safety is no longer perceived to be an objective in airport operations but rather a constraint (Harris 2002, p. 6). To complicate further the situation, new hazards are slowly emerging and the existing ones are becoming more difficult to manage (especially with the changing technology).

There is a growing emphasis on third party risk as another important factor in all airport safety considerations because airports attract huge volumes of human traffic and people who live close to these facilities suffers an involuntary risk of living next to airports. Even though there is a low probability of air traffic accidents occurring (like one in a million), the local risk level associated with air traffic disasters is significant. Concerning this observation, Price (2008) reports that, The resulting annual probability of an accident at a typical large airport is therefore much greater than the small probability of being involved in an aircraft accident as a passenger (p. 23). Furthermore, Price (2008) explains that air traffic accidents normally occur within the vicinity of the airports (during take-offs and landings).

Based on the above understanding, airports need to have strong safety measures to mitigate any risk of an accident. It is therefore important to uphold airport security to prevent the occurrence of airport attacks and uphold the high safety standards associated with industry. The effectiveness of guaranteeing high safety standards within our airports will therefore ensure that there is reduced crime, reduced terrorism and reduced instances of illegal trade within our borders. The importance of airport security can therefore not be underestimated because it serves different purposes including protecting the airport and country from any threatening events, to reassure the traveling public that they are safe and to protect the country and their people (House of Commons 2010, p, 3). The U.S. Federal Aviation Administration also emphasizes this point by asserting that, The goal of aviation security is to prevent harm to aircraft, passengers, and crew, as well as support national security and counter-terrorism policy (Burke 2008, p. 23).

This paper seeks to investigate the safety considerations for a commercial airport based on the current security threats that face modern airports today. To have a correct conceptualization of the research problem, this paper will be categorized into five sections. The literature review will be relied on to provide a proper model framework for analyzing the research problem. Here, the works of previous researchers will be evaluated to establish what other people have written regarding the research topic. The next section will be the research methodology, which will elaborate how the findings of the study were arrived at. This will be a thought out account of how the findings of the study were reached and why some of the research tools were used. The final section of this paper will be the conclusion section. This section will reinforce the findings of the study and open the outcomes to more scrutiny.

Literature Review

Safety considerations for a commercial airport have been analyzed from different angles. One aspect that has been evaluated by many researchers is the policy aspect of safety consideration for airport designs and operations (Harris 2002, p. 6). Different countries have different policies, but lately, most of these policies have been harmonized to international safety standards. Such standards have been developed by different organizations including the United Nations International Civil Aviation organization (ICAO) which was formed to regulate air traffic operations around the world (Harris 2002, p. 6). The formation of such organizations and policies started after the Second World War where airports started to report huge volumes of commercial air traffic. This period also characterized the evolution of aircrafts from small propeller driven machines to large aircrafts that can travel halfway around the world and carry more than 500 people in the same trip (Wittes 2009). Throughout this transition, air travel has not been as dangerous as other forms of transport. Partly, the main fact that has led to this observation is the formulation of common standards for aerodrome design. Wittes (2009) explains that, Todays ICAO Annex 14, dealing with Aerodrome Design and Operations, is a comprehensive document covering standards and recommended practices for aerodrome physical characteristics, obstacle restrictions, visual aids, electrical systems, aerodrome services and maintenance (p. 33). From the above assertion, Wittes (2009) notes that policy provisions have ensured that different aspects of airport design are safe. Furthermore, most of these policy provisions are renewed annually to ensure they cover all aspects of airport safety (today).

The standards for operating procedures in different commercial airports around the world have also been harmonized to reduce the risk of accidents in airports. This is another safety measure identified by Harris (2002) as having contributed to increased safety standards in commercial airports today. In reference to this observation, Harris (2002) emphasizes that:

The introduction of standard operating procedures employed by airport operators, airlines, pilots, air traffic control organizations, as well as the companies that provide important services such as ground handling and re-fuelling, have played a very important role in airport safety (p. 5).

Through the above assertion, there is a common agreement among all stakeholders that safety precautions are often added to an already safe system by improving the standard operating procedures in commercial airports. The effectiveness of these procedural operating standards cannot be underestimated because they cover most aspects of an airports operations, including airfield operations, all operations at the apron and all sensitive areas in airport safety such as gates and maintenance warehouses (Harris 2002, p. 8). For instance, most airports around the world have a provision for the maximum speed that a car should be driven on the apron and the stipulated distance for vehicles driving behind aircrafts with running engines. Similar provisions also define the rules for crossing taxiways. In fact, many airports have more stringent rules for any vehicle driving in the runways or any contact that is to be made with the control tower (Harris 2002, p. 8).

Similar rules and procedures also apply for airport personnel who control aircrafts. These rules are usually meant to safeguard the personnel and the aircrafts (Vicente 2004). For instance, all personnel are normally required to wear earmuffs and visible jackets when they are on the airfield so that they are visible to the pilots. Moreover, airport personnel are usually required to stand at a safe distance from the aircraft. These rules and procedures are normally inculcated into the safety culture of the aviation industry during the training period of new personnel.

Training is another safety aspect that has been identified by many researchers such as Filipczak (1996) because they highlight this aspect of air traffic control to be important in maintaining airport safety. Vicente (2004) purports that, it is vital for a safety culture to be engrained from the top management downwards, including the notion of a just culture, whereby reporting of safety hazards and occurrences is encouraged, with the intention of learning from these events and discussing solutions, which leads to a continuous reduction in the rate of accidents (Vicente 2004, p. 3).

Many organizations are involved in training airport personnel on the right safety standards to adopt. Most of these organizations vary in different countries. However, the Airport Council International (ACI) is very vibrant (internationally) in the training of airport personnel and imparting new knowledge on various aspects of airport safety. Such training normally occurs in short courses such as the ACI Global Safety Network Course (Swezey 1992, p. 219). Concerning such courses, Howell (1989) explains that, Airport Staff can obtain the ACI Global Safety Network Diploma after the completion of the three modules on: safety management systems at aerodromes, airside safety and operations and emergency planning and crisis management (p. 121). Training is therefore perceived to be a critical aspect of airport safety because poorly trained personnel are more prone to making security errors (which may turn out to be fatal).

Technology, systems and equipment are perceived to be tools that can greatly improve airports safety if properly used and improved. More importantly, the adoption of new technology in airport safety has greatly improved airport safety standards around the world. Different areas, influencing airport safety (such as new lighting systems, precision approach and landings systems, surface movement radar, visual docking guidance systems, and automated meteorological systems) have greatly benefitted from improved systems and equipment. These airport control fields are just a few areas that have benefitted from the improvement of systems and equipment.

The greatest advantage of using systems and equipment in maintaining airport safety is that they can be improved often. The use of modern safety systems and equipment in fire fighting and rescue missions is testament to the evolution of technology in improving airport safety (Swezey 1992, p. 219). Over the decades, other systems and equipment (used in emergency and evacuation situations) have also been improved using new systems and equipment. However, the entire notion of improving safety measures is to reduce the reliance on emergency and evacuation systems. Nonetheless, though this fact stands, it does not demean the importance of using modern equipment and systems in emergency services. Rough weather conditions that are known to worsen airport safety are also mitigated using modern systems and equipment in air traffic control. For example, advanced surface movement guidance and control systems have been widely adopted in many airports as an advanced tool to guide pilots during night landing and in times of rough weather (Swezey 1992, p. 219). These systems work the same way as traffic lights because they act as a clearance for landing. There are ongoing efforts in research and development to devise new safety measures to be engrained on the airports cockpit so that pilots can know their aircrafts position on the airfield and where other vehicles or moving objects are located on the same platform. It is estimated that testing such systems will commence soon and such equipment should be available in the market sooner (Swezey 1992, p. 219).

Safety management systems have also been identified as important tools for the maintenance of a good safety environment in the airport. The safety management system is nothing more than a procedural and structural way of managing airport operations such as structures, accountabilities, policies, procedures and similar aspects of importance to airport operations. ICAO is normally known as the main oversight body for the implementation of safety management systems. It works by having a strong regard to local aviation regulations and international aviation regulations. For instance, since the year 2003, most airports around the world have been required to have a manual that stipulates how all equipment and procedures (used in the airport) work (Vicente 2004, p. 3). The safety management system has replaced an older type of safety precaution that relied on periodic audits to ensure airport safety procedures were upheld. In relation to the establishment of a safety management system, Vicente (2004) recommends that all airports should have a safety management committee that includes all stakeholders who control the operations of all airport departments (including the apron, taxiways and runways). Through the establishment of the safety management committee, airport accidents such as runway incursions can be prevented. Nonetheless, the establishment of a safety management system requires many safety assessments to be done within specific intervals of times. Within each safety assessment, a risk assessment is done to reduce or eliminate the possibility of an accident occurring. Aerodrome safety has been upheld in many airports in this way.

There are certain structural designs that have been pointed out by Vicente (2004) to be important in the reduction of airport accidents and the improvement of airport safety. One such improvement is the establishment of fewer crossings on the runways. This can be done by changing the layout and design of the airport. The establishment of perimeter taxiways is also another strategy that can be used to improve airport safety, although many airports around the world find this strategy to lack feasibility because of a lack of space.

The provision of safety guidance materials has also been identified by some researchers such as Vicente (2004) as being vital to the improvement of airport safety. Concerning this identification, Vicente (2004) says that, Industry guidance material has been produced on the elimination or reduction of major risks such as runway incursions, excursions and confusion (p. 34). Currently, many issues are being reviewed as part of important air safety precautions. For instance, runway excursions are being reviewed for the risk of poor braking or aircrafts deviating from the runway due to poor weather. There are even more concerns currently being expressed about the presence of runway debris on the aircraft pathways which may potentially cause aircraft accidents during take-offs and landing. Some of this debris can cause severe mechanical malfunctions such as the presence of stone-sized objects, which may be sucked into aircraft engines (thereby causing mechanical failure). Similar objects may also be sucked into an aircrafts fuel tank, thereby blocking the fuel pathway. In Chicago, OHare airport has been identified to suffer such security risks because litter, rocks and unwanted materials are identified to characterize the airports environ (thereby posing a strong security threat to the aircrafts that land or take-off from the facility) (Airport Internationals US Correspondent 2009, p. 1). Most of these litter and unwanted materials were left on the airport during the construction of the taxiways and the expansion of the runways. Referring to the runway debris at O hare airport, Airport Internationals US Correspondent (2009) explains that:

The construction materials were found lying on demarcated runway safety areas at the ends of the airports newest runway and this concerned the debris found on the runways themselves: these safety areas being used in the event of emergency aircraft take offs or landings (p. 14).

At the same airport, there were other security threats on the runway, which emanated from the authorization to use airport facilities without properly training airport employees on the same (Guzzo 1988, p. 63). For example, some airport officials drove around undesignated areas of O Hare airport because they were not trained to properly use airport facilities.

Like runway excursions, runway incursions have also been identified as a real security threat to airport operations. A recent report detailing the risks of runway incursions and excursions have painted a grim picture on airport security by highlighting that passengers are often safer when they are airborne than when they are on the ground (Consumer Affairs 2009, p. 1). Partly, this security risk is attributed to runway incursions, which is identified by Consumer Affairs (2009) as any incident involving an unauthorized aircraft, vehicle, or person on a runway (p. 1). Over the years spanning the 2000s period, incidents of runway incursions have been on the rise. The year 2004 alone played host to a 38% increase in runway incursions in America (Consumer Affairs 2009, p. 1). Again, in 2008, more than 24 serious runway incursions were reported in the US. Some of these incidents were mere accidents brought about by poor weather while others were caused by negligence and other human errors (Reason 1990). In the US alone, several airports have been identified as bearing the greatest threats to runway incursions and excursions. These airports are located in Baltimore; Boston; Charlotte, North Carolina; Chicago; Fort Lauderdale, Florida; Los Angeles, New York City, Philadelphia; Phoenix; San Francisco; and Washington, D.C (Consumer Affairs 2009, p. 1). In 2005, an incident of airport incursion was reported at Chicago midway when an aircraft skid off the runway (due to bad weather), thereby causing four fatalities and 18 injuries. In California, another incident involving a jetliner flight which was trying to land at Bob Hope airport caused more than 44 injuries when it skid off the runway due to a lack of enough safety zones on the highway (Consumer Affairs 2009, p. 1). Due to such safety concerns, the FAA has listed more than 1000 airports in the US alone for not complying with the stipulated safety zone procedures. About a quarter of the listed cases are said to pose big threats to the safety of the passengers (Consumer Affairs 2009, p. 1).

However, concerning runway excursions and incursions as possible security threats, there are specific physical and training measures that have been taken to reduce such risks. Some countries are warming up to the challenges of such eventualities. For example, some nations are building longer runways (more than the recommended) to internally mitigate the risk posed by runway excursions. The establishment of an arrestor bed at the end of the runway is also another measure taken by airports to prevent runway excursions (Consumer Affairs 2009, p. 1). These risk mitigation measures are however done within the provision of ICAO regulations. Many airport authorities are further exploiting the possibility of mitigating other risks such as runway confusion and wrong runway operations.

However, the above measures are identified to (still) be insufficient at curbing all the possible threats to airport security. For example, there are other threats identified by Consumer Affairs (2009) concerning the location of certain international airports around wetlands and trees as another issue that greatly contravenes airport security because such environments attract animals and other living creatures to inhabit airport environs. Bird strikes are the greatest threat to airport security emanating from the close proximity of airports to wetlands, grasslands and forested lands. In fact, many airport officials facing this threat perceive the threat of bird strikes to be omnipresent. Airport threats of this nature have been reported in many parts of the world, with the most recent (and notable) airport security threat detected involving a flight take-off from New Yorks LaGuardia Airport in 2009 (Consumer Affairs 2009, p. 1). Hundreds of geese, which were wandering on the runway, obstructed the flight take-off. However, there were no deaths reported (Consumer Affairs 2009, p. 1).

Many aviation authorities such as the US federal Aviation Administration (FAA) have stressed the importance of airport authorities to mitigate the risk of bird strikes because airfields should not have any form of floating debris around their vicinity (Wagner 2012, p. 1). Nonetheless, not many airports around the world comply with set regulations regarding the topography of airport environs. For instance, few airports comply with the provision that grasslands surrounding the airports should not be more than six inches long. In addition, fewer airports comply with the regulation requiring all paved surfaces around airports to be free from all forms of vegetation.

The development of residential homes around airports has also been identified as another issue contravening airport security in many parts of the world (McNeil 2010, p. 1). Growing human populations in major urban centers around the world has exacerbated this problem. This increase in population has consequently led to a surge in housing developments, which have created more pressure to use idle airport land. Some of these developments have been necessitated by the growing pressure among investors to build commercial centers around airports to take advantage of the immense business opportunities, which exists from airport services. Such establishments include hotels, restaurants, recreational facilities and the likes. Due to these factors, pilots have been forced to fly dangerously close to residential and commercial establishments built around airports.

The danger posed by the establishment of residential and commercial buildings next to airports is increased by the threat o

Aim

There have been many developments in the field of aviation ever since the introduction of aircrafts. Different techniques and aids are constantly being improved for the execution of safe and smooth landings so as to complete this trickiest phase of a flight with less difficulty and more perfection. The aim of this paper is to look into the characteristic features of various prominent precision approaches such as, Instrument Landing System (ILS), Microwave Landing System (MLS), Wide Area Augmentation System (WAAS) and Local Area Augmentation System (LAAS); their components, the principle of operation; their limitations and probability of improvements in future. It also focuses on the comprehensive study of the future precision approach system called Smart Path, a ground based augmentation system, developed by Honeywell, and selected by FAA as an upcoming replacement for ILS in its Next Gen program. This paper also evaluates the importance of these systems in providing safety and reducing operational expenditures of airlines. Hence, the aim of this paper is to analyze the adequacy and accuracy of the landing aids and their implementation with respect to their requirements and practicability in aviation at present and in the years to come.

Executive Summary

Landing is the most crucial and demanding phase of a flight. For a smooth and safe landing of an aircraft it is necessary that the pilot is assisted with some landing aids. There are several technological navigation aids that help in the execution of a precision approach and landing.

The ILS is a combination of both approach lighting and radio beacons including their best qualities within one system. Though it is an important landing aid providing the lateral and vertical guidance necessary for a precision approach but in view of the future aviation requirements, it has certain limitations which prohibit or restrict its use in many circumstances.

MLS offers many advantages over ILS besides overcoming its confines. Accurate precision navigation guidance is provided by this system relative to the alignment and landing of aircraft. It is appropriate for the autoland approaches where the aircraft is controlled by the equipment as it allows safer landings in extreme weather, with zero visibility.

Further, two augmentations systems are developed, known as LAAS and WAAS, to assist the GPS in the civil aviation with space based navigation. Global, standardized navigation services for all types of aircraft operations and all phases of flight can be made available with the use of differentially corrected GPS service, with the support of WAAS and the LAAS.

The requirement of GPS to get some assistance from the ground for rapid descending of an aircraft quite near to the ground paved the way for a ground based augmentation system (GBAS), which is also called Smart Path and is an effective system to smarten up air-traffic control. The replacement of ILS with GBAS technology has been recognized crucial for the enhancement of the air traffic capacity in the FAAs Next Gen program and Euro controls Single European Sky ATM Research Program. GBAS avionics have become an integral part of most current-production Airbus and Boeing aircraft. GBAS, described as SmartPath by Honeywell, is the initial stage of an infinite plan to refurbish air-traffic control.

The limitations of older technologies in ensuring safe landings where only short-length airstrips are available due to deserts or vegetated areas and in rough seas, led to the development of autoland system. Different climate and weather conditions affect the approach and landing phase of an aircraft considerably. Autoland systems are used to ensure a safe landing in extreme weather conditions and intense levels of visibility.

Advancements in avionics such as the SmartPath, introduced by Honeywell and the autoland system are not only cost effective but also suggest an increasing role for flight inspections chances, in the coming years, with respect to the navigation and landing aids.

Development in Aircraft Landing Technology

Introduction

Landings are the most crucial phase of a flight and carry significant safety messages with their execution. Missing of any essential correction and misjudgments at any point may result into an immense calamity. Most of the accidents are caused by inaccurate procedures in the landing phase (Horne 2011).

The complexities involved in the process generate chances of accidents taking place. So, in order to return the aircraft back to the earth safely and firmly, a skillful execution of the landing phase is highly required. It is essential to have an ideal knowledge of the various aspects such as: what should be the speed, knowledge regarding the rate of descent and glide path along with an absolute judgment of glide path (Nirjharini 2011).

To achieve a smooth and secure landing a number of technological navigation aids can be used by the pilot. Initially, there were only people-powered landing aids where people used to stand on the field with flags to provide direction to the aircraft. They used to wave red, green, or white cloths symbolizing different signals (Mola n.d.).

Gradually, the radio controllers were developed to provide some landing aid to the pilots. Moreover, red or green lights were also utilized to present the view of the runway threshold and sides in the airport. This helped the pilot to judge the remaining distance and angle to be taken for landing (Mola n.d.).

History

Development of aircrafts: Before the existence of airports and introduction of any landing aids, the pilots used to be guided by the direction of the wind, in landing the aircrafts. With the constant growth of air traffic, the airports were developed and landing was restricted to definite directions. The complexities faced during the landing of an aircraft were resolved to some extent with the development of the landing aids that enabled pilots to stick to a correct landing course, thus making it safer (Mola n.d.).

Use of lights: Airports began the use of lights in the late 1920s.Landing fields were marked with rotating lights that offered guidance to the pilots in the dark. The use of approach lighting in the airports in the early 1930s helped the pilots by guiding them to take proper descent and ensured that they were on the right direction. The approach path was called the glide path or glideslope (Mola n.d.). In course of time, the International Civil Aviation Organization (ICAO) provided a standardized form of the colors of the lights and their rates of flash to be recognized in all over the world (Molan.d.).

Introduction to slop-line approach: The slope-line approach was the first system implemented as landing aids that was a cone shaped formation of rows of lights (funnel) providing guidance to the pilot to reach the finishing point of the runway. In case of some deviation to the right or left, or too high or low other patterns of lights were exhibited. Although this system, developed in 1940s was economical to build and operate but some constraints restricted it from being used in certain airports (Molan.d.).

Introduction of radio navigation aids: Next, radio navigation aids were developed for getting assistance in landing. In 1929, the establishment of a four-course radio-range with the power of Morse code signals guided the pilot in taking right decisions in maneuver. Another types included a low-frequency radio beam, which flickered outward from the landing point forming a v shape. Although, the wide space offered for flying towards the end of the runway offered convenience to the pilot but the narrow space at the landing point often misled the pilot in striking the center point for landing. The method of tuning into a certain frequency at a distant checkpoint, and using a stop watch to come down at an exact rate to the touchdown area also proved to be complicated (Molan.d.).

Development of Instrument Landing System: The instrument Landing System was the next step in the development of landing aids. Tests of this system began in 1929, and it got approval for installation in 1941 at six locations by the Civil Aeronautics Administration (CAA).In the Instrument Landing System the approach lights and radio beacons both were included to build a system combining the best features of both. The pilot could view the glide path personally with the help of the electronic picture of glideslope in the cockpit instruments. The ILS system was tested for the first time on January 26, 1938, when a scheduled U.S. passenger airliner Pennsylvania-Central Airlines Boeing 247-D, from Washington, D.C., to Pittsburgh, using ILS landed in a snowstorm (Molan.d.).

Adoption of the standardized ILS: Several types of ILS system were tried before standardizing it. At last, a system comprising a localizer for the lateral guidance, a glide path or landing beam to provide vertical guidance, and two marker beacons denoting the progress of approach to the landing field, was adopted as a standardized form of ILS. The pilot was enabled to receive the information with the help of the equipment in the airplane so that he could see the runway and bring the aircraft on the right flight path (Mola n.d.).

In 1949, the International Civil Aviation Organization (ICAO) adopted the standard set by the U.S. Army, by introducing an ILS with a higher frequency transmitter to reduce static and create straighter courses, for all member countries. It was called the Army Air Forces Instrument Approach System Signal Set 51. The first ILS equipment, without any visual aids, achieved a safe landing in 1960s (Molan.d.).

During World War II, the development of radar showed the way to the introduction of a new precision-beam landing aid which is known as the ground control approach (GCA). GCA performed well in association with the ILS in making the landing easier for the pilots at more active airports. By 1948, distance measuring equipment (DME) for measuring the distance of the airplane from the ground was set up. The data acquisition relating to the planes distance from the ground was made available with the help of distance measuring equipment (DME). Along with the air-route supervision type of radar other radar were also installed at a number of airports in the mid-1950s helping air traffic controllers in dealing with air-traffic efficiently (Molan.d.).

Instrument Landing System:

ILS description: The ILS is an important landing aid providing the lateral and vertical guidance necessary for a precision approach. A precision approach suggests an approved procedure of descending an aircraft with the help of a navigation facility associated with a runway. An integrated ILS system along with the approved approach procedure leads to the proper execution of a precision approach (Carnegie 2008).

ICAO Categorization with respect to RVR: The current ILS was developed and standardized in the United States during the World War II. Three categories of visibility are defined by ICAO relative to the runway visual range (RVR) (Powell 1981).

This categorization is based on the principle that there should be adequate short visual reference for the range of permitted decision heights. These categories are defined graphically in the following illustration (Pallet & Coyle 1993).

Category 1: Category 1 illustrates that there should be minimum 200ft decision height and runway visual range of 800m for the possibility of successful approach.

Category2: A high possibility of success rate is described below 200ft decision height and runway visual range from 800m, and as low as 100ft decision height and 400m runway visual range (Pallet & Coyle 1993).

Category3: Category 3 illustrates the visual range of minima 200m, with external visual reference during the final phase of the landing down to the runway.

Category3B: The visibility to and along the runways and taxiways is to be sufficient for visual taxiing equivalent to runway visual range of minima 50m (Pallet & Coyle 1993).

Category3C: No external visual reference is required to and along the surface of the runway and taxiways (Pallet & Coyle 1993).

Main Components of the ILS: The total system is divided into three parts consisting of a transmitter on the ground and receiver and signals in the aircraft. A localizer is provided for the lateral steering for front-course and back-course. Vertical navigation, for the front course, is provided by the glide slope. For getting distance checks, marker beacons are used (Powell 1981).

The above illustration is depicting the vertical needle of the localizer and the horizontal needle of the glide slope. The dots are representing center of the ILS or distance from center of ILS. The round button is used for the airport selection. The signs provided by marker beacons are shown below. Important runway information is put on view in floating text beside instrument (040_ILS Instrument Landing System n.d, Para 4).

Instrument landing system (ILS) provides accurate and reliable navigation facility to an aircraft in IFR conditions. In this system the position of the aircraft is ensured with reference to the instruments. ILS comprises four main instruments.

The above picture illustrates the sequence of 18 important tasks performed by the pilot in changing over from cruise flight to touchdown with the use of ILS (Niquette 1996).

Localizer

Ground Equipment: The localizer is the main component of the ILS. It makes the lateral guidance available. It is a VHF radio transmitter and antenna system with similar general range as VOR transmitters (between 108.10 MHz and 111.95 MHz).The frequencies are only on odd-tenths, with 50 kHz spacing between each frequency (Carnegie 2008, Para B.1).The transmitter and antenna are located on the centerline on the other end of the runway from the approach entrance. Some ILS systems also include the localizer back course which is normally available with a75MHz back marker facility or NDB positioned 3to 5 NM from touchdown. To ensure its positioning with specified tolerances the course is checked time to time (Carnegie 2008).

Signal Transmission: The localizer spreads out the signal in the air. These signals generate two vertical overlapping patterns identical to the shape of a fan. These patterns are aligned absolutely with the centerline of the runway. The right side of this pattern is symbolized by blue and is called the blue area. It is modulated at 150 Hz. The left side of the pattern which is symbolized by yellow is called the yellow area. It is modulated at 90 Hz. The overlap existing in the middle of the two areas is helpful in providing the signal relating to the runway. The navigational beam is regulated so as to enable about 700 ft wide track signal acquisition at the runway threshold. The localizer is recognized by a two-letter audio signal (preceded by the letter I for example I-OW) overlaying the navigational signal (Carnegie 2008).

Since the primary strength of the signal is aligned with the runway centerline, the reception range of the localizer is at least 18 NM within 10º degrees and at least 10NM between l0º to 35º of the on-track signal (Carnegie 2008).

Localizer Receiver: There is a localizer receiver in the aircraft which functions in amalgamation with the VOR receiver in a single unit to receive signals in the aircraft. The localizer and the VOR use common electronic circuits. There is a common frequency selector, a volume control, and ON-OFF control for the two receivers (Carnegie 2008, Para 5).

From left to right, the aircraft is 1° Right of course, two dots (turn left to return); On course; and 1° Left of course (turn right to return)(Wood 2008, Para 10).

On receiving a localizer signal, the vertical needle or the track bar(TB) is set in motion. Suppose, a final approach track is aligned north and south, an aircraft taking position in the east of the extensive centerline of the runway (position 1) is in the area modulated at 150 Hz, will avert the TB to the left. On the other hand, if the aircraft is taking position to the west of the runway centerline, the 90 Hz signal the TB will deviate to the right (position 2).Force is applied to the needle by both the angles in the overlap area. This force redirects the needle in the direction of the strongest signal which helps in placing the aircraft in accurate position. The point showing equivalent intensity of both the 90 Hz and 150 Hz signals, TB being centered, indicates the precision approach (Carnegie 2008, Para 10).

However, it is advisable that the pilot should set the track selector most of the times for the approach track. This is because the track selector setting in the localizer function is not dependable in most cases. The obstructions in between the transmitting antenna and the aircraft often cause difficulty in receiving the signals clearly. The weak signals make the vertical needle to deflect a little or indicate an OFF flag in front of it.

Glide Slope Equipment

Transmitter: The vertical guidance for the landing approach is provided by the glide slope which is formed with the help of a ground-based UHF radio transmitter and antenna system (Carnegie 2008). These channels in the u.h.f. band function at a range of328.6-335.4 MHz at 150kHz spacing. The frequencies, allocated to the glide slope, are paired with the localizer frequency as both serve the same runway (Powell 1981, p.70-71). The positioning of the glide slope transmitter is about 750 to 1,250 feet down the runway from the entrance, offset 400 to 600 ft from the centerline of the runway (Carnegie 2008).

The glide slope signal also consists of two beams where one beam lie on top of the other. These beams are adjusted at 90 Hz and 150 Hz. The signals spread out by the glide slope are aligned above each other and emitted mainly down the approach track. The thickness of the overlap area is 1.4º or.7º above and.7º below the optimum glide slope.(Carnegie 2008).

The adjustment of this glide slope signal varies between 2º and 4.5º above a horizontal plane. In view of obstructions along the approach path and the runway slope, it is adjusted between 2.5º to 3º.Several glide path angles along the glide slope may produce false signals. The false signal approximately 6º degrees above horizontal will be a mutual signal for the fly up and fly down commands and these commands will be reversed. The false signal at 9º will be sloping just as the true glide slope. However, there are no false signals generated below the genuine slope (Carnegie 2008, Para 11).

Signal Receiver: A UHF receiver is made available in the aircraft to receive the glide slope signals in combination with the VOR controls to receive the proper glide slope frequency by tuning it automatically when the localizer frequency is selected (Carnegie 2008).

A glide slope needle, positioned in conjunction with the TB, is set in motion by the glide slope signal. There is a special OFF flag for the glide slope needle which is visible in the navigation indicator in case of a weak signal. There is a constant deviation in the glide slope needle and it stops deflecting only after reaching that point where the signals overlie on one another. The needle deviates towards the stronger signal and slowly comes to the centered position horizontally when both the signals are equal indicating that the aircraft is proceeding in the right direction on the glide path (Carnegie 2008).

An accurate location relative to the approach path can be accessed by referring to a single instrument. The Glide Slope Signal Pattern figure, above, position1, illustrates that the aircraft is located in the center of the approach path as both the needles are in the centered position. In Position 2 it is evident that the aircraft needs to fly down and towards the left to rectify the approach path whereas position3 is shows the requirements to fly up and towards right for catching the proper path(Carnegie 2008, Para 12).

With the aircraft coming closer, the instrument picks up its operation accordingly. It is important that at this point of time; the pilot must monitor the deflection of the needle to know whether the aircraft is high, low or in a centered position (Carnegie 2008).

ILS Marker Beacon: The marker beacon is used for the modulation of signals. It radiates upwardly using the frequency of 75MHz (Powell 1981).These are low-power transmitters; that operate with 3 W or less rated power output. There are some preset points along the approach track in Instrument Landing System which are recognized by the marker beacons to provide information regarding distance from the runway. They radiate an oval beam upward from the ground at an altitude of 1,000 ft. which is 2,400 ft long and 4,200 ft wide and considerably increases with higher altitudes (Carnegie 2008).

Descriptions of the ILS components

Here is a three-dimensional depiction of the Instrument Landing system. We can see the Localizer antennas close to the end of runway (Wood 2008, Para 4).

Outer Marker (OM): Within 250 ft of the extended runway centerline, the outer marker is located 3 1/2 to 6 NM from the entry. At around 1,400 ft above runway elevation a point is marked by OM crossing the glide slope vertically. It also marks the estimated point from where an aircraft starts the final approach plan. The signal is adjusted at 400 Hz, which is a low tone but easy to hear with continuous Morse code dashes. For receiving these signals, a 75 MHz marker beacon receiver is incorporated in the aircraft. The pilot can hear a tone over the speaker or headset in harmonization with flashing of a blue light. Geographical conditions may affect the positioning of the outer marker. So, a DME unit may be used to enable the pilot in making a positive position fix on the localizer. An NDB is used in place of the OM in the majority of ILS installations (Carnegie 2008, Para 14).

Middle Marker (MM): The middle marker is located about.5 to.8 NM starting from the threshold and going along the complete runway centerline. It intersects the glide slope at about 200 to 250 ft above the runway elevation and is close to the missed approach point for the ILS Category l approach (Carnegie 2008).

Back Marker (BM): About four to six miles from the runway threshold, usually, the back course marker (BM) is located. These are located on the localizer back course. The BM low pitched tone (400 Hz) is heard as a series of dots(Carnegie 2008,para4).

The aircrafts white marker beacon light is enlightened by these dots. The BM can be replaced by an NDB or DME fix quite often (Carnegie 2008).

Lighting Systems

There are many approved runway environment lighting systems in the ILS system. These lighting systems ensure the safe landing of the aircraft by providing proper visual guidance to the pilot. These are: approach light system (ALS), sequenced flashing light (SFL), touchdown zone lights (TDZ) and centerline lights (CLL-required for Category II [Cat II] operations.)(Carnegie 2008,para 4).Out of these any one or all the lighting systems may be provided at a specified facility (Carnegie 2008).

Runway Visibility Measurement: Before coming downwards to the decision height (DH) or the missed approach point (MAP) it is essential that the pilot has a clear view of the approach path with the help of the appropriate visual aids. The transmissometer is located adjoining the runway to provide visibility information. The photo electric cell receiver separates the light source by 500 to 700ft.The relative transparency or mistiness of the air is measured by the receiver, connected to the instrument readout in the airport tower. The readout is standardized in feet in respect of the visibility and is known as the runway visual range (RVR) (Carnegie 2008).

Runway Visual Range (RVR)

At the runway the maximum distance utilized for taking-off or landing is known as RVR. It is specified with light or markers so that it can be seen from a height matching to the pilots average eye-level at touchdown. It is normally expressed in hundreds of feet e.g. RVR24signifies that the visual range along the runway is 2,400 ft. Visibility differs in different runways so the RVR value differs accordingly. Even different points along the same runway may have varying visibility. To deal with this condition, there are many types of equipment fixed at the departure end and the central point of the runway. Runway Visual Range reports denote the capability of a pilot to have the visibility of the runway in the touchdown zone. However it is to be noted that the positioning of the transmissometer establishes the actual visibility at other points down the runway. RVR enables the pilots to decide their executions in the ultimate stages of an instrument approach. The information regarding the Runway visual range is sent to the ATC arrival control, and the control tower or FSS. The pilots are offered this information as per their requirement. The light settings can be adjusted on demand by the pilot. Two different light settings can be provided for the landing of consecutive flights. Since there are complex equipment involved, RVR is usually made available at busier airports only(Carnegie 2008).

NDBs

Supplementary aids like NDB also exist for assisting the pilot in reaching the final approach fix. It is a non-directional beacon which can be sited with the outer marker (OM) or back marker (BM) and also used to replace the OM or BM. Its transmitting power is about 25 watts (W) and frequency range is 200 kilohertz (kHz) to 415 kHz. The radio beacon can receive the signal spread out in the area of at least 15 nautical miles (NM)(Carnegie 2008).

ILS limitations

Even after providing navigation precision guidance well in the past so many years and adopting a lot of measures for improving its performance and consistency, the Instrument Landing System(ILS) has come up with certain limitations. In view of the future aviation requirements, the ILS has some basic limitations such as: site sensitivity and high installation costs; it adopts single approach path; multi path interference; and has only 40 channels (Carnegie 2008).

The limitations prevailing in the ILS generated a necessity of a more fool  proof landing aid that could prove to be accurate for safe landings. The following limitations in the ILS cause its degradation (Crabtree 2009).

• There are certain restrictions relative to ILS techniques and operations which affect the flight path flexibility and airport throughput (Crabtree 2009,para 6).
• ILS gets easily affected by signal interference due to weather and other impediments resulting in major chaos in the airport traffic, causing delays (Crabtree 2009).
• There are many ground related constraints with ILS. It requires a relatively flat terrain as ground irregularities and poor weather affect its performance (M.L.S. 1995).
• The channel range is limited to 40 channels only (M.L.S. 1995).
• ILS uses a single approach path causing much confusion and chaos in the air traffic control (M.L.S. 1995).
• It has a high user cost and is dependent on expensive ground equipment (Parkinson 1996).

• Basic ILS is suitable only for the FAAs non precision and Category I landing requirements and only the improved ILS system can execute a landing with Category III required accuracy (Parkinson 1996).
• Moreover, the noisy ILS signals need to be processed with a smoothing filter (Parkinson 1996).

Disasters with ILS

Although, ILS has been perceived as an efficient landing aid for past so many years, inaccuracy and errors in the guidance information through this system have led to several disasters in the aviation history (Phelan 2001).

A false instrument landing system (ILS) is assumed to have caused the disastrous Korean Air Boeing 747-300 accident at Guam in August 1997.The glideslope indication may have been a chief contributory factor to this mishap. Recent studies by Air New Zealand (ANZ), have declared that the problem may have led the crew to believe that they were on the correct descent when the aircraft crashed into Nimitz Hill 5km (3nm) from touchdown. ANZ believes that the new findings indicate that 40 other controlled flight into terrain (CFIT) investigations call for review now (Phelan 2001).

On July 29, 2000, during a standard instrument landing system (ILS) approach to Faleolo at night, an Air New Zealand Boeing 767 with 165 passengers and 11 crew on board commenced a go-around after descending to an altitude of about 400 ft, some 6 mi. short of the runway (ILS System Failure  A Free Lesson 2010, Para 2). It was revealed after thorough investigations that flawed guidance information was being transmitted by the ILS glide path (GP) transmitter. The cockpit GP and localizer indications were normal. The Civil Aviation Authority (CAA) of New Zealand has publicized the matter widely so as to warn the ILS operators about the risks involved with this approach. Hence, a valuable insight into the recognized weakness in ILS systems is provided by this serious incident. It has annunciated the necessity to adhere to ICAO standards and guidance material during ILS operations and maintenance to avoid extreme hazards (ILS System Failure  A Free Lesson 2010, Para 2).

Another instance indicating the failures of the ILS system came into light when a First Air Boeing 737-200, regi

Introduction

Over the ages, a great number of analysts have spoken about women leadership, their role, how they lead and the challenges they face when leading a company or an organization and how they have achieved good results in their leadership. It is imperative to note that leadership is a process whereby a person socially influences another individual or a group to perform a task and achieve desired goals (Fabra, & Cesar, 2009, p. 603).

In the UAE, women have in the past struggled to get job promotions and occupy leadership positions amidst many challenges brought about by many beliefs expressed in their culture and religious practices. Al Gharaibeh says that traditions and laws primarily hold women back from their full leadership participation in the economy and politics of the nation (2011, p. 96). This essay will explore the perceptions that surround women involvement and participation in leadership. Besides, it will critically analyze how culture, religion and perceptions impact on women leadership in the UAE.

Women leadership in UAE

In the United Arab Emirates, the achievements of women over the years has immensely impressed me and made me understand that the seeds of the great effort that women planted are bearing fruits today. It is imperative to note that in UAE, up to and until the 1970s, there were hardly any educated women, save even those who could occupy leadership positions (Fatima, 2001, p. 33). Research studies indicate that this could have been attributed to the traditional practices that surrounded and defined gender roles among Muslims.

Indeed, and as Fatima points out, even if women during that time intended to occupy leadership positions, they were still illiterate and less prepared. Al Gharaibeh in his publication says that discrimination against women that has been carried forward into the constitution of the land was caused by adherence to historical remnants of a society that does not exist anymore (2011, p. 96). None of them could have wished to rise and challenge men in a male-dominated society.

Today, a lot has changed as the UAE country has begun to depend on women for leadership since they are vital for social and economic developments. According to the president of the UAE, Sheikh Zayed bins Sultan Al Nayan, women in this region have been major contributors and stimulus for economic growth (Arab Law Quarterly, 2000, p. 416). The development history of UAE from a desert land to desert farms, landscaped gardens, high towering skyscrapers, modern hospitals, and schools, without doubt, owes its brilliance to evolvement and involvement of women (Mora & Ferrer-i-Carbonell, 2009, p. 586).

Religion, Culture, and feminism

It is traditionally known that the place for the Arabic woman is the home. Her life revolves around her family; her children, her husband and generally keeping the home habitable. According to Mora & Ferrer-i-Carbonell, the place of a Muslim woman has been defined by religion and culture. Efforts to create change in the perceptions culture and religion have on women have met diverse setbacks. Changing deep-rooted religious and cultural practices requires people to change their attitudes. In her article, Fatima Mernissi says that Everyone is afraid of change, but Muslims are more so because what is at stake is their fantasies about power (Mernissi, 1987, p. 10).

Indeed, this is true in the sense that men in the Muslim society, backed by their culture and religion, dominate most leadership positions and feel that creating room for women to lead alongside them will rob them of their power fantasies. The gender debate on culture and feminism continues to point out the roles of Islam women in UAE. Khalaf & Alkobaisi argue that the cultural practices that have been in this country have continued to undermine, marginalize and place women employees in adverse positions of subordination (Khalaf & Alkobaisi, 1999, p. 290).

They further claim that cultural attitudes on feminism have been negative especially on the leadership and roles of women in a society dominated by males. Al Gharaibeh says that discrimination against women is one key indicator of the failure of a political system in the democratic process, while participation is considered to be one of its most important elements (2011, p. 99). This is indeed true since the Quran states that both genders are equal, it also indicates that women are supposed to be subordinates and serve their husbands (Khalaf & Alkobaisi, 1999, p. 290). This combined with culture has seen women in UAE experience discrepancies in job descriptions, seniority, and education.

According to Mernissi (1987, p. 14), despite many campaigns and achievements made in having women leaders, UAE women still face diverse challenges in their bid to occupy leadership positions in their own country or to work outside the UAE. Some of the challenges include religion that requires them to keep themselves veiled and be submissive (Mernissi, 1987, p. 14). She argues that as such when employed, the effect of their cultures makes them assume less important sections and make important decisions in the nation.

For instance, one of the problems that have impeded the ability of women to make decisions is a cultural setback that requires women to be submissive and seek permission from their male partners before engaging themselves in any decisions. This is indeed a challenge as it takes a long time before a woman can embark on serious business since most decisions on any important idea are made by men. This adversely affects their ability to make decisions that will grow the business bearing in mind that they have to compete equally with other male business rivals in the design market.

Besides, organizational structure, like in our partnership, is a representation of a business program that has a chain of command whereby officers of the company and the employees are categorized in units that show their level of importance and responsibility (Khalaf & Alkobaisi, 1999, p. 290). The organizational structure defines the relationship that should exist between the chain of command regardless of gender. With this in place, a company stands a better chance of minimizing costs and maximizing results since everyone in the company will know how to interact with one another and with the departments in the company (Madar Research Group., 2004, p. 10).

Also, workers get to understand their place and their duties. Tanmia (2006, p. 167) points out that an effective system of good governance forms its foundation in an organizational structure that is competently built. This kind of organizational structure ensures that there is increased productivity through assigning areas of duty and power to leaders, ensuring that the staff are not under too much pressure or are neglected based on gender. Additionally, Tanmia argues that right from the perspective of gender, stereotypes emerge such as the one that ascribes to the inability of a woman to manage personal business well without getting assistance from a male person (Tanmia 2006, p. 167).

In agreement, Al Gharaibeh says that womens freedom to enter the public sphere reflects to a large extent the nature of the political and social system of a country, and their equal access to political processes reflects the principles of social justice in a society (2011, p.100). For this reason, important ideas and decisions that women make must wait for men to approve. However, it is imperative to note that today, there are organizations that are managed professionally to assist in raising the level and expertise of women involvement in business enterprises without being sidelined by gender and other cultural stereotypes.

Khalaf & Alkobaisi express that unemployment among females in UAE is acute especially among those women who are educated (Khalaf & Alkobaisi, 1999, p. 290). On the other hand, Clark, Frijters & Shields feel that although this may be argued to be a general trend across the divide, it is worth to note that how women have been subjected to societal treatment is not the same at all compared to their fellow men (Clark, Frijters & Shields, 2008, p, 109).

The significance of this can be better appreciated when one takes into consideration the fact that women make up a large portion of those graduating from universities, as compared to men (Marshall, 1995, p. 15). Women who are educated are thus not willing to join the construction industry, in effect increasing the number of unemployed women in the society. This is like creating a sustainable source of income, given that women entrepreneurs tend to deviate from the normal and conventional fields of investing, such as construction and oil extraction and processing industries.

Cultural change

According to Tanmia (2006, p. 167), women evolvement and leadership in UAE draws its beginning from universal education. It is imperative to note that education has empowered UAE women to compete for leadership positions like men do. As such, Fatima Mernissi points out that women have unveiled themselves, and that todays UAE is in a situation where fundamentalist men and women and nonfundamentalist women have a conflict of interest (Mernissi, 1987, 11).

Besides, she argues that in schools, both men and women have the same educational privilege (Mernissi, 1987, p.11) and that the number of women is now high above that of men and their illiteracy has dropped by approximately 11.3% (Clark, Frijters & Shields, 2008, p, 109). In higher colleges of technology, 70 % of students and in Universities such as Al Ain, over 15,000 students (60%) are women. In 2002, university chairs were occupied by approximately 57% (Dencker, 2008, p. 460).

Through education, women have been able to obtain and occupy leadership positions, act independently and be able to reason. Reports from statistics carried out by the UN indicate that leadership among women in UAE countries has been contributed by the blossoming of women in terms of education (Arab Law Quarterly, 1996, p. 59). From this backdrop, it is evident that women in the entire United Arab Emirates (UAE) bloc are indeed emerging as equal competitors as their counterpart men.

According to Bahgat (1999, p. 132), due to the high levels of education, women in the UAE have been opened to countless career choices. Baghat argues that as such, they have been able to rise to leadership positions in diverse roles such as doctors and teachers (Bahgat, 1999, p. 132; Neal, Finlay & Tansey, 2005, p. 245). The number of total workforce and heads of departments in UAE countries is made up of 20% women but is much higher in the government sectors with over 27% of them being decision-makers, 57% heading banking sectors and 40% labor force (EL-Haddad, 2006, p. 286; Webb, 1997, p 159).

It is imperative to note that the degree with which women have advanced in UAE countries puts them in a position where they can be directly involved in making decisions involving the country just like it is with the western countries. In UAE, there are over 23,000 businesswomen with a total of 62 billion dollars in their account (Gallant, & Pounder, 2008, p. 29). By 2008, it was reported that a total of ten business executives who were women from the Middle East made their record as among the best 100 bankers worldwide, indicating how women have not only excelled in conducting business but are also great entrepreneurs and skilled in the business world (Grandey, Cordeiro & Crouter, 2005, p. 319).

This is an interesting point of departure for UAE women in the sense that although the capital has been a major impeding factor in their growth in the business world, they are not badly off. Indeed, the aforementioned factors are great incentives for UAE women who are planning to engage in leadership activities, including those who are in various businesses (Gaad, 2006, p. 291).

According to Stephenson (2010, p. 231), both the public and private sectors play an integral role in building the economy of the United Arab Emirates country. While the public sector is run and managed by the government, the main players in the private sector are individuals who set up their businesses and run them as private entities (Al-Jenaibi, 2010, p. 236; Behery, 2008, p. 860; Bristol-Rhys & Rugh, 2009, p. 766). Each of these sectors has unique merits and demerits. For instance, some individuals would prefer to be employed in the public sector largely due to job security and a stable salary. However, the private sector may also promise better salaries among other fringe benefits that come along with various jobs being offered. The working environment may be enjoyable alongside flexibility at work which enhances creativity as well as skill development.

According to Claros & Zahidi (2005, p. 453), the existence of women leaders in businesses in UAE and their variance has been remarkable over the past ten years both in terms of quality and number. This has also been the trend across the world. Leadership in the private sector is steadily supplementing the public sector through spontaneous growth (Claros & Zahidi, 2005, p. 453; El-Baz & El-Sayegh, 2010, p 1088). Moreover, small businesses have remarkably shaped the way business is done and as a result, the UAE economy is experiencing growth mainly due to the existence and expansion of small businesses.

Women and leadership progress

Dating back in history, women have been embroiled in a struggle in the society to prove their worth, and also to take their rightful places in the society as far as all aspects of life are concerned (Al-Tarrah, 2010, p. 22). Al Gharaibeh explains this situation by saying that in UAE Women suffer the harmful, life-threatening effects of traditional and cultural practices that continue under the guise of cultural and social conformism and religious beliefs that discriminate between genders (2011, p. 102).

This struggle, Al Tarrah (2010, p. 22) argues, has been extended to obtaining leadership positions, where women are trying to prove that they are as good as men when it comes to managing entities. Up to now, women in UAE, due to the already industrialized, strong and vibrant economies, seem to have made significant gains in terms of leadership. It is estimated that women run and control about a third of all business enterprises in this society. These businesses owned and managed by women are playing a very significant role in the economy of these countries, and their impact in the whole society in extension cannot be downplayed.

Women leadership, as a result, has continued to attract the attention of scholars in society. There is interest in analyzing how this historically discriminated segment in the society is fairing on in a field that has been controlled by men for a very long time now (Anon., 2011, p. 288). Al Gharaibeh says that however, women often feel embarrassed to complain, and as a result, they remain silent because they know they will not be supported, and because they fear of sullying their reputation or ruining their career (2011, p. 101) To this end, several studies have been conducted, addressing various attributes of this field.

This ranges from the challenges that women face in their leadership roles, their rate of success and such other factors. Businesswomen in the UAE have especially attracted a lot of attention from these scholars. This is given the fact that the women of this region are especially known for their subordinate role in the society because men have traditionally dominated many spheres of leadership in this region for a very long time (Randeree, & Chaudhry, 2007, p. 225). They control business, family issues, politics, and such other important areas. Heckathorn (2002, p. 20) points out that Sheikh Fatima, UAEs First Lady, has played a great role in ensuring that women have made great achievements in leadership roles.

She established an organization for women in 1975 as well as an umbrella society for all women called UAEs women Federation. At the beginning, the federation aimed at linking UAE women with international organization, raising their cultural standard through planned activities, ensuring needy women is reached by social care and services, eradicating illiteracy and developing self-esteem and image of women (Heckathorn, 2002, p. 20; Miller, 2001, p. 160). Today, Miller (2001, p. 160) argues that through the federation, women have risen to occupy positions of leadership in fields such as insurance, designing, engineering, cosmetics, banking, architecture, and all media aspects. Some examples of women leaders in UAE include Sheikh Zayed, UAEs First Lady, and Farida Kamber, an emirate businesswoman (Heilmann, Bell & McDonald, 2009, p. 90).

The latter, besides being a leader of an interior design company, has won numerous awards. It is imperative to note that the first lady has been on a campaign for UAE women to members of the national council, members of parliament and work in media houses. She has desired to have women from all walks of life have full rights in decision-making processes, participate in politics and be equal with male their compatriots (Omair, 2009, p. 416). Some of them had been motivated from the early beginnings from the success witnessed in their male counterparts.

The fact that men have always succeeded in leadership has greatly boosted the confidence of UAE women to start and independently lead others or run their enterprises without relying on men (Randeree, 2006, p. 65). On the same note, the cultural dilemma that had faced most women in past has indeed gone down and as a result, women are no longer viewed as house-keepers but as equal competitors both in the academics and in the business world

In my perspective, women play a momentous role in facilitating change and development in the UAE countries. According to Al-Ajmi (2001, p. 103), their daily contribution to the socio-economic well being of the nation cannot be overstated here. As indicated, the areas of importance where UAE women play an integral leadership role are in the private sector and even the public sector (Al-Ajmi, 2001, p. 103). In private sectors, their contributions are seen through the establishment of businesses. Since not all women in the UAE are finding it easy to compete against men in leadership, many of them have been encouraged through women organizations not to give up as the society has a place for women especially in leadership in the business cycles.

Indeed, this situation has prompted many women entrepreneurs to compete favorably and stiffly with their male counterparts (Richardson & McKenna, 2006, p 18). It is interesting to note that despite the challenges experienced by women entrepreneurs in UAE, there are still a host of motivating factors that keep them going as observed. For instance, as aforementioned, it has been noted that women form a huge chunk of university graduates in UAE in the sense that most of them are indeed well educated, a scenario that put s them into favorable competing ground in terms of leadership with another individual especially men. This is especially so considering that they are the majority in the society, making up about fifty-one percent of the worlds population. This being the case, it is important to note that empowering women in society will go a long way in helping everyone there.

Leadership development

As indicated earlier, it was traditionally known that the place for the Arabic woman is the home. Her life revolves around her family; her children, her husband and generally keeping the home habitable. As such, it attracts a lot of attention to see how UAE women have developed in their leadership styles and are now spreading their wings far and wide, beyond the confines of the four walls of their houses even to leadership in the society. Richardson & McKenna (2006, p 18) argue that women in UAE have indeed been inspired to focus their effort on taking leadership roles bearing in mind that the formal sector is largely dominated by males and few women find employment opportunities there.

The available opportunity in the government public sector is also highly competitive compelling women to seeking leadership roles to increase their efforts (Richardson & McKenna, 2006, p 18). It is also worthy to note that UAE countries seem to be offering vast leadership opportunities for women even though they need to step out of their comfort zones and prove their worth in a male-dominated society (Metle, 2002, p. 259). Opportunities for leadership are vast. As such, the available leadership opportunities for women in the UAE can only be explored if the right effort, commitment, and knowledge are put in place (Metle, 2002, p. 259).

It is important for women engaging in leadership to get to know that real commitment and application of stringent leadership skills cannot be evaded at any given time during any operation. Also, women need to understand that whenever they set their focus on leadership, they should expect challenges that come with it. Al Gharaibeh says that women are discriminated against in the workplace based on their gender, despite their broad participation in the workforce. Discrimination occurs subtly as well as blatantly. An example of subtle discrimination is in the choice of careers(2011, p. 103). As most studies have pointed out, most women performing leadership roles reaches a period when they are faced with challenges.

Many women leaders in UAE have indicated that in their leadership, they have been faced with a myriad of challenges but they have always been determined to remain afloat and persistent. It is instructive to note that both men and women in the UAE have unique roles that they play in society (Rose, 2005, p. 460). Although they have equal opportunities in life, the latter has historically struggled to assume leadership positions in a male-dominated world. Despite this, the case of the developed world is rather unique since women seem to be at the center stage of development controlling many sectors in the economy. These developed economies are being transformed by females (Talhami, 2004, p. 16).

My main worry is that employment opportunities for women in the construction and public works sector cannot sustain the population for a longer period of time. For example, jobs in the construction sector last as long as the construction boom lasts (Hutton, 1995, p. 64). The jobs from this sector are more or less cyclical, meaning that they are unable to provide a stable or high-quality employment in the future. Those who are working in the construction and public works sector are less likely to be able to enter into employment in other sectors when the construction boom comes to an end. They are likely to revert to the unemployed class, in effect widening the unemployment rates in the country.

Even though employment is generally high in UAE, the case is different when one considers the women who are in leadership in the construction and public works industry. This is given the fact that they are unable to work in this industry, where most of the employment opportunities are to be found (Metle, 2001, p. 320). As such, it indicates that unemployment among the male population is declining, that among the female population is on the rise.

Conclusion

To sum up, the challenges posed by gender on the issue of leadership is not limited to the UAE only. Even though no evidence segregate enterprise ownership along gender line, current statistics, as already mentioned, reveal that a lesser percentage of organizations are owned by women while the remainder are owned by males. Furthermore, there is minimal statistical evidence on the growing number of women engaging in decision making and leadership activities. As already noted, the UAE economy has grown, resources are abundant, and the government support women leadership. As such, the economy provides the best opportunity for women to excel in leadership roles.

Additionally, women have also extended their struggle to obtaining leadership positions, where women are trying to prove that they can perform as men or even in a better way contrary to what the society has belied in for decades now. Up to now, women in the wider United Arab Emirates (UAE), owing to the well-developed economies, seem to have made huge strides in terms of leadership. It is approximated that women run and control about thirty percent of major business organizations in the UAE. These businesses owned and managed by women are playing momentous roles in boosting the economic development of this economic bloc. Therefore, their impact on modern society cannot be underestimated.

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