Various aircrafts have been inducted into air fleets across the globe. Though many have managed to create history through their operations during combat and training, the F-117 Nighthawk made history when it was first inducted in 1988 as part of the United States Air Force (Crickmore, 2005). The plane itself was a break from all previous technology and offered something to aviation that no other plane at the time offered stealth technology. Though the technology had been under development and was employed in various arenas, this was the first aircraft to have been built, structured and devoted around the entire concept of stealth Technology. Though retired from service in 2008 in light of newer developments such as the F-22 Raptors and the F-35 Lightning, it is clearly understood that the development process and experience from this plane has led to the ground setting for the ones to follow.
Its initial conception was on the basis of requirements of stealth technology. Necessity is the mother of invention and that phrase works well for the F-117 Nighthawk given it was inducted on the basis of the requirements of the USAF during the Vietnam War (Crickmore, 2005). A project developed by Lockheed, the Vietnam war highlighted a new chapter in aviation history the need for stealth. American Air Force bombers were facing serious difficulties when conducting bombing runs during combat. They would often be shot down or easily observable during bombing runs because Soviet manufactured surface to air missiles at the time were technologically advanced to down most bombers available to the USAF.
The entire concept of stealth aviation was developed through a paper by Pyotr Ya Ufimtsev. A mathematician by profession, he was a Russian citizen who developed a calculated and logically solution to undetected flight (Global Aircraft.Org). According to him, the radar cross sections could be evidently monitored along a wings surface and its edge. This would provide the reasoning for hiding from radar detection but since this idea was formulated in the 1960s, technology at that time could not reap the benefits. Lockheed, however, exploited the principle and began development on the project during the 1970, when advanced technology to provide stability to the program was available.
The program that actually developed the F-117 Nighthawk was called the Senior Trend. As part of a highly confidential development program, the F-117 Nighthawk was formulated alongside the Have Blue project. This project was the start of the entire Senior Trend project and the development of the F-177. All it took were two 60 in size, model prototypes to convince the United States Air Force that this was a good investment. As such, the contract was awarded to Lockheed, under their advanced Development Projects.
The aircraft itself is not a bomber or a fighter jet. Based on the designation it has received, the aviation instrument is often called the F-117A. The letter at the end (A) signifies its capabilities which in the aviation field, reflect that it is a ground attack aircraft. However, many contest that the F reflects its properties as a fighter jet as well. It is true that the F-117 can take part in air-to-air combat however, its main operational effectiveness lies in dealing with ground attacks (Holder, Wallace, 2000).
Associated technology
The basis of the technology used to develop the F-117A has been entirely based on VLO techniques. These are called the Very Low Observable techniques, reflecting stealth technology and radar detection mentioned earlier. As Ufimtsev paper on cross sections and radar visibility stated, this plane was designed on that principle and perfected upon it. The entire plane was made making sure that the design would correspond to a low radar cross section. Thus, the diamond like shape and the wing structure basically reflects on the use of this scientific finding (Jenkins, 2000).
Another important factor in the construction of the F-117A was the use of Radar Absorbing Materials. These materials are generally used to allow fighter aircrafts to absorb radiation levels and save them from radar detection. However, these materials were already in use during the time of the development works of the F-117A, but required refinement. The technology used in the F-117A is superior to earlier forms of RAM, which though effective, could not provide the same feasibility that was required for a stealth fighter. Therefore, the shape of the entire aircraft had to be altered to ensure that the RAM was working on maximum utility, providing a competitive advantage to the aircraft. Science was used to prove that for the detection range of an aircraft to fall by 10 times, it was essential to decrease the RCS of the aircraft by a numerical factor of 10,000 (456FIS.ORG, 1999). This could only be done by altering the shape of the aircraft, which was done.
Then, to reduce the radiation emissions from within the aircraft, more steps had to be taken to make sure that the F-117A obtained stealth. This was done by powering the windows of the internal cockpit with metallic film. This metallic film not only reflected energy from outside, but at the same time, did not allow energy from inside the cockpit to seep out either. This was further enhanced by coating the entire aircraft with a sheet of Radar Absorbing Material. They were placed as tiles on the aircraft. However, the technology with this developed with time as well as initially, to stick the RAM on the plane, glue would be used. Not only was this extremely expensive but at the same time, it was time consuming and tedious and required a lot manual labor (456FIS.ORG, 1999). This was later replaced with spray systems which did exactly the same job, cheaper and more environmentally friendly.
Another technological and scientific improvement that was made was related to the exhausting of the plane itself. All exhausts in planes release infra red, which is often very easy to detect, thus spoiling the entire purpose of stealth. Thus, the exhaust shafts were lined with infra-red and electromagnetic tracers which would reduce their detectable emissions to provide the aircraft with stealth capabilities. Another method that was also used was applying specific grids that were lined with the same technology use to give the stealth fighter stealth capabilities through the use of RAMs (456FIS.ORG, 1999).
Tricking SAM radars and air-borne interceptors was the key to the stealth abilities of the aircraft. Without being able to manipulate these two factors, the survivability of the aircraft itself would be under serious question. Thus, based on scientific data and the latest technology, it was found that to go undetected from these sources it was not necessary to fly at supersonic speeds (456FIS.ORG, 1999). Instead, the fighter flies at subsonic speeds. The engines were designed in a way to encompass this technology. It was decided that the entire aircraft would be powered by an engine that did not have an after burn. Second, the frame of the entire aircraft had to be heat resistant. This would decrease emissions from the frame which also produce a infra red wavelength detectable by most radars.
Design and specifications
The F-117A is equipped with a variety of technologies. However, when analyzing it design and specifications, it is important to consider the three underlying areas of analysis
General Characteristics
Weapons armory
Performance
General Characteristics
The aircraft is operated by a one man crew. The aircraft itself has a wingspan of over 13 meters, and is characterized with a height of over 3.5 meters. Its length is approximately 20 meters. When unloaded, the aircraft has a flying weight of 13,380 kilograms (Global Security.Org). However, when loaded with weaponry, the aircraft can weight almost 10 kilograms more, taking the weight down to approximately 14,000 kilograms It generates its power through two massive engines, made by General Electric. They provide a power of 48.0 Kilo-Newton each (Global Aircraft.Org).
Weaponry
The F-117A is characterized for holding 2 internal weapon bays. This means that the aircraft can carry a load of heavy bombing material which includes laser guided missiles, and GPS guided Munitions. The cargo for the payload is often criticized by many researchers and defense analyst. The payload that the plane can carry is far lesser than what normal fighter planes can carry. This means that more F-117As are needed during bombing runs. However, given the stealth capabilities of the aircraft, the extra airplanes end up acting as force multipliers.
Certain upgrades have been made to the stealth fighter in terms of weaponry. Noting the above mentioned situation, in 2004, an F-117A was equipped with a JDAM bomb. This bomb alone weights 2000 pounds. Basically, the weaponry system was a problem for the F-117A, but latest upgrades such as the block II upgrade in 2006, has significantly enhanced the stealth fighters capabilities (Airforce-Technology.com).
Performance
The aircraft is not very fast as compared to other aircrafts. However, that is to preserve its stealth capabilities. Because of that, the aircraft does not touch supersonic speed, but can however travel faster than the speed of sound. It has a speed of approximately 993 kilometers per hour which is about 0.9 machs. It can travel 1720 kilometers without refueling and has a wing load of 330 kgm2 (Global Aircraft.Org).
Design
Holistically considering the dynamics of the aircraft, we can see that the design is shaped in such a way that it is optimum for operations. This is because the F-117A is edgy, and has a surface which is naturally designed to reflect hostile radar signals. The rough, edgy and RAM coated design does is that it reflects all hostile radar signals into narrower beams away from the source. The entire design is based upon saw tooth edges which trail across the aircraft. Not only have that, but the design materials used been titanium and aluminum. The usage of titanium has mainly been centered on the thrust areas and the exhaust areas of the plane. However, aluminum is the main component of the aircraft. The specifically V shaped tail is used to control the aircraft to a certain degree in high speed flight. The tail is also used to disperse off radar signals and infra red signals emitted by the plane itself. Since the entire design does not have any flaps as are placed in conventional aircrafts, upon landing, the F-117A has a very high speed. Thus, to slow it down, parachutes are often employed as a way of reducing speed.
Finally, the cockpit is condition with the conventional HUD. This display provides the same sources of information any other HUD does. However, the cockpit has one essential feature and that is the measurement of heat emissions and infra red radiation from the cock pit itself. These are monitored by onboard sensors at all time to ensure that no radiation is leaked outside the airplane to prevent detection. The aircraft on the whole has no radar navigation. This means that unlike conventional planes, the system used in this plane is entirely different. It uses infra red scanners to detect distances and navigations. There are a range of infra red systems involved, out of which the two most important are the forward looking infrared and the downward looking infrared. These systems are used for navigation and even targeting. The system is generally run by an automatic control unit which sequences and control operations. The pilot takes control during landing take off and in flight combat or special maneuvers. Otherwise, one benefit of the F-117A is that it is self reliant in terms of operations.
To ensure that no heat is lost and stealth is protected, the F-117A has all heat emitting points lined with gratings and RAMs (Global Aircraft.Org). The engines specifically are made in a way that its design reduces detect-ability. This is because the engines and their exhausts are very flat and wide in nature. Furthermore, the aircraft itself is air re-fuel able. Though now this is a necessity, at the time of induction this was something very new and the technology used was state of the art.
Production
The unit cost for one F-117A Nighthawk has been estimated to 42.2 Million US dollars. This is the fly away cost where as the entire development cost is often rounded as over 100 million US dollars (Global Aircraft.Org) During the initial years of production, the materials that were used were many of the spare parts from previous F-16 fighters and FA-18 Hornets. This lowered the development costs for the program significantly, but many critics claim this was to protect the secrecy of the program. Efforts to reduce the drag of 30 on engine usage potential were not handled properly and the program incurred a lot of costs because of that. A lot of time, money and effort were spent but there was no way the risk to stealth could be compromised.
Operational Feasibility and issues
Though the above part of the paper has clearly explained the positives of the operational effectiveness and performance of the stealth fighter, however, there was a reason for it to be decommissioned from the United States Air force in 2008. The F-117A has often been categorized as the Wobbly Goblin (456FIS.ORG, 1999), sometimes due to its shape and sometimes due to its level of efficiency. The following part of the paper will examine the problems associated with its design and performance, that some believe, are the reasons behind its decommissioning and discontinuation from production lines.
Instability of Design
One of the major problems with the F-117A Nighthawk is the instability of its design. As mentioned earlier, the design has gone through thorough processes to bring it to a point of stealth activity. However, during the production the focus has always been on the reduction of RCS The radar Cross Section. This is the basics of stealth technology and allows aircrafts to go undetected in the air. However, the shape and design that follows to achieve these performance enhancers, results in severe reduction of aero dynamic performance (Jenkins, 2000). The special air navigation automated system mentioned above is to an extent necessary for this stealth fighter. Because the fighter is so unbalanced on three axes, it is essential to have a fly-by-wire navigation system to control in flight performance. This means that flight data has to be carefully and constantly managed and monitored to provide a smooth flight, without instability. These computers are then required to constantly make flight corrections to ensure that the instability is curtailed to a minimum.
Fighting ability
Another serious drawback of the aircraft is its quest for stealth. Because of its quest for stealth, and its primary purpose, the aircraft loses out on effective combat abilities. For one, most dedicated fighter planes have serious afterburners and the ability to fly at supersonic speed. However, for stealth fighters like the F-117A, such conditions are not applicable because they can neither fly at supersonic speed, nor do they have after burners. The primary reason behind this fact is that afterburners produce heat which gives out infra red signatures (Crickmore, 2005). Furthermore, travelling at the speed of sound produces a sonic boom, which can result in the enemy locating the target. The supersonic speed also severely heats the entire aircraft, giving off another heat signature, which can lead to detection (Crickmore, 2005). Though these factors have been reduced in newer stealth fighters, the F-117A had to face the brunt because its operational effectiveness in terms of maneuverability was seriously compromised.
Flight modes
At certain points in the flight transition of stealth aircrafts, they can become visible to radar for a while. This is generally because of the mode they are flying in but the F-117A had a serious issue with its weapons bay. The ability to fly in stealth was drastically reduced every time the aircraft armed and launched missiles towards enemies. The reason for this was that since all weapons are internal and held in the very internal bay, radars cannot detect it. However, in moments where the bay is opened to drop the payload, even older radars can detect the aircraft since the RAM covering the aircraft at the point is not present (Zobel, 2008). The weapons bay is open. This aspect creates a serious vulnerability, as it did for the F-117A. Highly responsive defense system can zone in on the stealth fighter immediately. If the fighter does not regain stealth fast, there is a good likelihood it will be attacked, and thus reducing its operational effectiveness.
In the time of the F-117A, these issues were quite pertinent and needed to be addressed. However, with the induction of newer bombers, especially those like the B-2 or F-22, these issues have been greatly resolved. In fact, now, stealth fighters are so smartly equipped, that they can regain their stealth mode after the deployment of payloads in less than a second. This makes the best defensive systems ineffective. However, during the time of the F-117A, such technology was either not developed or not employed. Either way, it provided the aircraft with a serious disadvantage.
Payloads
As described earlier, one of the reasons for internal payloads and internal fuel systems is because of the factor of stealth. If these payloads are removed and placed outside, stealth is drastically compromised. However, when internal bays are used, other factors associated with performance are drastically affected, as they were for the F-117A.
One major problem for the Nighthawk was the fact that it could only carry two laser GPS guided weapons. This is particularly lower than that you would expect for a fighter aircraft. Especially since comparable fighter aircrafts which are not stealth carry payloads often 3-5 times more (Zobel, 2008). For the United States Government this became a serious issue. This is because when the F-117A could not carry enough payloads, more aircrafts had to be deployed for effective operations. This issue not only substantially increased costs to develop such aircrafts but at the same time increased maintenance costs of the aircrafts themselves. Even though critics claim that this was not a serious disadvantage, especially since the costs for supporting aircrafts are drastically reduced, even so, this was a critical issue that was analyzed before the discontinuation of the F-117A Nighthawk.
Maintenance
One of the biggest issues with the F-117A was its maintenance costs. Since the technology used is highly intensive and sensitive, careful oriented care was needed to maintain the fighter air craft. The basic issue that arose was with the fighter skin. Since this is tiled onto the aircraft, they have to be constantly maintained to ensure that they keep sticking to the frame of the aircraft. At the same time, the materials used, specifically RAMs, have to constantly cleaned, maintained and kept in tip top condition for them to disperse radar signals accurately and effectively (Global Security. Org). This, however, increased the cost of maintenance for the aircraft substantially.
Now, updated technology that is used in the B-2 stealth bomber fixes this issue accurately. Otherwise, when it was the case for the F-117A, the sealing processes were so tedious and expensive that it would take hours to reseal tiles that were unsealed to maintain them. Even the slightest cut in the tiles is enough to reduce the stealth capabilities of the fighter drastically. Thus, critical care and attention to this aspect required intensive care which was often hard to provide due to the high costs and time structures involved.
The F-117A Nighthawk was used in a variety of missions. However, its main debut was perhaps the Gulf War where it achieved its first monumental assignment. The fighter was a very good addition to the fleet and at the time of operation Desert Storm flew approximately 1300 sorties (FAS.org). They were categorized as one of most efficient bombing machines available at the time because they struck around 1600 targets, both due to their excessive use and their stealth abilities. Because of their prevailing success rate of 80, they were one of the very few aircrafts allowed to operate in bombing missions inside Iraqs Capital, Baghdad (FAS.org).
However, the story took an unusual twist in later years. Since the aircraft was being employed in all forms of combat, the United States decided to use the same tactic with the Kosovo conflict in 1999. However, this was met with a very monumental attack on one of the F-117As. At that time, it was not conceived that the fighter plane could be targeted given its enormous strength and stealth abilities. Also, its past history had reflected the same idea. However, one customized Surface to air missile (SA-3 Goa) was used against the aircraft which hit with pin point accuracy. It was noted that these newly developed weapons were capable of detecting the aircraft for a short moment of time by wavering the wavelength at unusually long levels (FAS.org). This meant that the stealth capabilities of the F-117A had been compromised since within no time, other countries would develop similar technologies. This was perhaps the dawn of the age of the retirement of the aircraft. This was particularly because after the downing of the first F-117A, the entire wreckage was never recovered. It has been widely cited that soviet intervention led to a deep analysis of the technology used in the development of the aircraft. This also meant that similar products would be launched by rival countries and the competitive advantage of the Nighthawk would be lost. Thus, began the spiral to try and wind the product up and develop a new one in light of the circumstances.
Even so, many critics still believe that the aircraft should not have been abandoned the way it was. They cite the fact that this is a conspiracy against all other fighter jets since the top elite of the USAF want to preserve the F-22A which is often termed as the Ultimate Fighter. They also cite the ability of the F-117A aircraft to carry payloads internally as an advantage. They claim that currently, even the F-22A carries payloads externally, under its wings. This reduces its stealth abilities but the fact is often disregarded by the USAF, which is surprising to many.
However, based on the evidence provided above and scientific research conducted in the analysis of the F-117A fighter, it is clear that the technology used at the time was state of the art. However, with the improvement of computers and technology, the usage of the F117-A was becoming redundant day by day. Its moment of retirement was near as it could not compete with newer developed aircrafts who were not only using the same basis of technology (Stealth) but also more efficiently. This is not to say that the F-117A was not an effective machine. In light of the time it was used in, it was operationally effective to a great deal. However, now, with bombers such as the F-22 which can reach stealth levels comparable to the revered B-2 stealth Bomber, the F-117A had to be retired. The F-22, often held as the successor to the F-117 is regarded as the new age of stealth technology. Not only can it fly at supersonic speeds without compromising on its stealth, it can also carry greater payloads and requires far lesser maintenance requirements for its RAMs, making it a good substitute to the F-117A.
To say that the F-117A has been retired would not be entirely correct. Without doubt they have been decommissioned from active service but they are still being stored in Tonopah, Nevada. Their wings and tails have been removed but they have been kept in a situation where they can be actively called to duty in a moment of crisis (Air Force- Technology.com).
Its initial conception was on the basis of requirements of stealth technology. Necessity is the mother of invention and that phrase works well for the F-117 Nighthawk given it was inducted on the basis of the requirements of the USAF during the Vietnam War (Crickmore, 2005). A project developed by Lockheed, the Vietnam war highlighted a new chapter in aviation history the need for stealth. American Air Force bombers were facing serious difficulties when conducting bombing runs during combat. They would often be shot down or easily observable during bombing runs because Soviet manufactured surface to air missiles at the time were technologically advanced to down most bombers available to the USAF.
The entire concept of stealth aviation was developed through a paper by Pyotr Ya Ufimtsev. A mathematician by profession, he was a Russian citizen who developed a calculated and logically solution to undetected flight (Global Aircraft.Org). According to him, the radar cross sections could be evidently monitored along a wings surface and its edge. This would provide the reasoning for hiding from radar detection but since this idea was formulated in the 1960s, technology at that time could not reap the benefits. Lockheed, however, exploited the principle and began development on the project during the 1970, when advanced technology to provide stability to the program was available.
The program that actually developed the F-117 Nighthawk was called the Senior Trend. As part of a highly confidential development program, the F-117 Nighthawk was formulated alongside the Have Blue project. This project was the start of the entire Senior Trend project and the development of the F-177. All it took were two 60 in size, model prototypes to convince the United States Air Force that this was a good investment. As such, the contract was awarded to Lockheed, under their advanced Development Projects.
The aircraft itself is not a bomber or a fighter jet. Based on the designation it has received, the aviation instrument is often called the F-117A. The letter at the end (A) signifies its capabilities which in the aviation field, reflect that it is a ground attack aircraft. However, many contest that the F reflects its properties as a fighter jet as well. It is true that the F-117 can take part in air-to-air combat however, its main operational effectiveness lies in dealing with ground attacks (Holder, Wallace, 2000).
Associated technology
The basis of the technology used to develop the F-117A has been entirely based on VLO techniques. These are called the Very Low Observable techniques, reflecting stealth technology and radar detection mentioned earlier. As Ufimtsev paper on cross sections and radar visibility stated, this plane was designed on that principle and perfected upon it. The entire plane was made making sure that the design would correspond to a low radar cross section. Thus, the diamond like shape and the wing structure basically reflects on the use of this scientific finding (Jenkins, 2000).
Another important factor in the construction of the F-117A was the use of Radar Absorbing Materials. These materials are generally used to allow fighter aircrafts to absorb radiation levels and save them from radar detection. However, these materials were already in use during the time of the development works of the F-117A, but required refinement. The technology used in the F-117A is superior to earlier forms of RAM, which though effective, could not provide the same feasibility that was required for a stealth fighter. Therefore, the shape of the entire aircraft had to be altered to ensure that the RAM was working on maximum utility, providing a competitive advantage to the aircraft. Science was used to prove that for the detection range of an aircraft to fall by 10 times, it was essential to decrease the RCS of the aircraft by a numerical factor of 10,000 (456FIS.ORG, 1999). This could only be done by altering the shape of the aircraft, which was done.
Then, to reduce the radiation emissions from within the aircraft, more steps had to be taken to make sure that the F-117A obtained stealth. This was done by powering the windows of the internal cockpit with metallic film. This metallic film not only reflected energy from outside, but at the same time, did not allow energy from inside the cockpit to seep out either. This was further enhanced by coating the entire aircraft with a sheet of Radar Absorbing Material. They were placed as tiles on the aircraft. However, the technology with this developed with time as well as initially, to stick the RAM on the plane, glue would be used. Not only was this extremely expensive but at the same time, it was time consuming and tedious and required a lot manual labor (456FIS.ORG, 1999). This was later replaced with spray systems which did exactly the same job, cheaper and more environmentally friendly.
Another technological and scientific improvement that was made was related to the exhausting of the plane itself. All exhausts in planes release infra red, which is often very easy to detect, thus spoiling the entire purpose of stealth. Thus, the exhaust shafts were lined with infra-red and electromagnetic tracers which would reduce their detectable emissions to provide the aircraft with stealth capabilities. Another method that was also used was applying specific grids that were lined with the same technology use to give the stealth fighter stealth capabilities through the use of RAMs (456FIS.ORG, 1999).
Tricking SAM radars and air-borne interceptors was the key to the stealth abilities of the aircraft. Without being able to manipulate these two factors, the survivability of the aircraft itself would be under serious question. Thus, based on scientific data and the latest technology, it was found that to go undetected from these sources it was not necessary to fly at supersonic speeds (456FIS.ORG, 1999). Instead, the fighter flies at subsonic speeds. The engines were designed in a way to encompass this technology. It was decided that the entire aircraft would be powered by an engine that did not have an after burn. Second, the frame of the entire aircraft had to be heat resistant. This would decrease emissions from the frame which also produce a infra red wavelength detectable by most radars.
Design and specifications
The F-117A is equipped with a variety of technologies. However, when analyzing it design and specifications, it is important to consider the three underlying areas of analysis
General Characteristics
Weapons armory
Performance
General Characteristics
The aircraft is operated by a one man crew. The aircraft itself has a wingspan of over 13 meters, and is characterized with a height of over 3.5 meters. Its length is approximately 20 meters. When unloaded, the aircraft has a flying weight of 13,380 kilograms (Global Security.Org). However, when loaded with weaponry, the aircraft can weight almost 10 kilograms more, taking the weight down to approximately 14,000 kilograms It generates its power through two massive engines, made by General Electric. They provide a power of 48.0 Kilo-Newton each (Global Aircraft.Org).
Weaponry
The F-117A is characterized for holding 2 internal weapon bays. This means that the aircraft can carry a load of heavy bombing material which includes laser guided missiles, and GPS guided Munitions. The cargo for the payload is often criticized by many researchers and defense analyst. The payload that the plane can carry is far lesser than what normal fighter planes can carry. This means that more F-117As are needed during bombing runs. However, given the stealth capabilities of the aircraft, the extra airplanes end up acting as force multipliers.
Certain upgrades have been made to the stealth fighter in terms of weaponry. Noting the above mentioned situation, in 2004, an F-117A was equipped with a JDAM bomb. This bomb alone weights 2000 pounds. Basically, the weaponry system was a problem for the F-117A, but latest upgrades such as the block II upgrade in 2006, has significantly enhanced the stealth fighters capabilities (Airforce-Technology.com).
Performance
The aircraft is not very fast as compared to other aircrafts. However, that is to preserve its stealth capabilities. Because of that, the aircraft does not touch supersonic speed, but can however travel faster than the speed of sound. It has a speed of approximately 993 kilometers per hour which is about 0.9 machs. It can travel 1720 kilometers without refueling and has a wing load of 330 kgm2 (Global Aircraft.Org).
Design
Holistically considering the dynamics of the aircraft, we can see that the design is shaped in such a way that it is optimum for operations. This is because the F-117A is edgy, and has a surface which is naturally designed to reflect hostile radar signals. The rough, edgy and RAM coated design does is that it reflects all hostile radar signals into narrower beams away from the source. The entire design is based upon saw tooth edges which trail across the aircraft. Not only have that, but the design materials used been titanium and aluminum. The usage of titanium has mainly been centered on the thrust areas and the exhaust areas of the plane. However, aluminum is the main component of the aircraft. The specifically V shaped tail is used to control the aircraft to a certain degree in high speed flight. The tail is also used to disperse off radar signals and infra red signals emitted by the plane itself. Since the entire design does not have any flaps as are placed in conventional aircrafts, upon landing, the F-117A has a very high speed. Thus, to slow it down, parachutes are often employed as a way of reducing speed.
Finally, the cockpit is condition with the conventional HUD. This display provides the same sources of information any other HUD does. However, the cockpit has one essential feature and that is the measurement of heat emissions and infra red radiation from the cock pit itself. These are monitored by onboard sensors at all time to ensure that no radiation is leaked outside the airplane to prevent detection. The aircraft on the whole has no radar navigation. This means that unlike conventional planes, the system used in this plane is entirely different. It uses infra red scanners to detect distances and navigations. There are a range of infra red systems involved, out of which the two most important are the forward looking infrared and the downward looking infrared. These systems are used for navigation and even targeting. The system is generally run by an automatic control unit which sequences and control operations. The pilot takes control during landing take off and in flight combat or special maneuvers. Otherwise, one benefit of the F-117A is that it is self reliant in terms of operations.
To ensure that no heat is lost and stealth is protected, the F-117A has all heat emitting points lined with gratings and RAMs (Global Aircraft.Org). The engines specifically are made in a way that its design reduces detect-ability. This is because the engines and their exhausts are very flat and wide in nature. Furthermore, the aircraft itself is air re-fuel able. Though now this is a necessity, at the time of induction this was something very new and the technology used was state of the art.
Production
The unit cost for one F-117A Nighthawk has been estimated to 42.2 Million US dollars. This is the fly away cost where as the entire development cost is often rounded as over 100 million US dollars (Global Aircraft.Org) During the initial years of production, the materials that were used were many of the spare parts from previous F-16 fighters and FA-18 Hornets. This lowered the development costs for the program significantly, but many critics claim this was to protect the secrecy of the program. Efforts to reduce the drag of 30 on engine usage potential were not handled properly and the program incurred a lot of costs because of that. A lot of time, money and effort were spent but there was no way the risk to stealth could be compromised.
Operational Feasibility and issues
Though the above part of the paper has clearly explained the positives of the operational effectiveness and performance of the stealth fighter, however, there was a reason for it to be decommissioned from the United States Air force in 2008. The F-117A has often been categorized as the Wobbly Goblin (456FIS.ORG, 1999), sometimes due to its shape and sometimes due to its level of efficiency. The following part of the paper will examine the problems associated with its design and performance, that some believe, are the reasons behind its decommissioning and discontinuation from production lines.
Instability of Design
One of the major problems with the F-117A Nighthawk is the instability of its design. As mentioned earlier, the design has gone through thorough processes to bring it to a point of stealth activity. However, during the production the focus has always been on the reduction of RCS The radar Cross Section. This is the basics of stealth technology and allows aircrafts to go undetected in the air. However, the shape and design that follows to achieve these performance enhancers, results in severe reduction of aero dynamic performance (Jenkins, 2000). The special air navigation automated system mentioned above is to an extent necessary for this stealth fighter. Because the fighter is so unbalanced on three axes, it is essential to have a fly-by-wire navigation system to control in flight performance. This means that flight data has to be carefully and constantly managed and monitored to provide a smooth flight, without instability. These computers are then required to constantly make flight corrections to ensure that the instability is curtailed to a minimum.
Fighting ability
Another serious drawback of the aircraft is its quest for stealth. Because of its quest for stealth, and its primary purpose, the aircraft loses out on effective combat abilities. For one, most dedicated fighter planes have serious afterburners and the ability to fly at supersonic speed. However, for stealth fighters like the F-117A, such conditions are not applicable because they can neither fly at supersonic speed, nor do they have after burners. The primary reason behind this fact is that afterburners produce heat which gives out infra red signatures (Crickmore, 2005). Furthermore, travelling at the speed of sound produces a sonic boom, which can result in the enemy locating the target. The supersonic speed also severely heats the entire aircraft, giving off another heat signature, which can lead to detection (Crickmore, 2005). Though these factors have been reduced in newer stealth fighters, the F-117A had to face the brunt because its operational effectiveness in terms of maneuverability was seriously compromised.
Flight modes
At certain points in the flight transition of stealth aircrafts, they can become visible to radar for a while. This is generally because of the mode they are flying in but the F-117A had a serious issue with its weapons bay. The ability to fly in stealth was drastically reduced every time the aircraft armed and launched missiles towards enemies. The reason for this was that since all weapons are internal and held in the very internal bay, radars cannot detect it. However, in moments where the bay is opened to drop the payload, even older radars can detect the aircraft since the RAM covering the aircraft at the point is not present (Zobel, 2008). The weapons bay is open. This aspect creates a serious vulnerability, as it did for the F-117A. Highly responsive defense system can zone in on the stealth fighter immediately. If the fighter does not regain stealth fast, there is a good likelihood it will be attacked, and thus reducing its operational effectiveness.
In the time of the F-117A, these issues were quite pertinent and needed to be addressed. However, with the induction of newer bombers, especially those like the B-2 or F-22, these issues have been greatly resolved. In fact, now, stealth fighters are so smartly equipped, that they can regain their stealth mode after the deployment of payloads in less than a second. This makes the best defensive systems ineffective. However, during the time of the F-117A, such technology was either not developed or not employed. Either way, it provided the aircraft with a serious disadvantage.
Payloads
As described earlier, one of the reasons for internal payloads and internal fuel systems is because of the factor of stealth. If these payloads are removed and placed outside, stealth is drastically compromised. However, when internal bays are used, other factors associated with performance are drastically affected, as they were for the F-117A.
One major problem for the Nighthawk was the fact that it could only carry two laser GPS guided weapons. This is particularly lower than that you would expect for a fighter aircraft. Especially since comparable fighter aircrafts which are not stealth carry payloads often 3-5 times more (Zobel, 2008). For the United States Government this became a serious issue. This is because when the F-117A could not carry enough payloads, more aircrafts had to be deployed for effective operations. This issue not only substantially increased costs to develop such aircrafts but at the same time increased maintenance costs of the aircrafts themselves. Even though critics claim that this was not a serious disadvantage, especially since the costs for supporting aircrafts are drastically reduced, even so, this was a critical issue that was analyzed before the discontinuation of the F-117A Nighthawk.
Maintenance
One of the biggest issues with the F-117A was its maintenance costs. Since the technology used is highly intensive and sensitive, careful oriented care was needed to maintain the fighter air craft. The basic issue that arose was with the fighter skin. Since this is tiled onto the aircraft, they have to be constantly maintained to ensure that they keep sticking to the frame of the aircraft. At the same time, the materials used, specifically RAMs, have to constantly cleaned, maintained and kept in tip top condition for them to disperse radar signals accurately and effectively (Global Security. Org). This, however, increased the cost of maintenance for the aircraft substantially.
Now, updated technology that is used in the B-2 stealth bomber fixes this issue accurately. Otherwise, when it was the case for the F-117A, the sealing processes were so tedious and expensive that it would take hours to reseal tiles that were unsealed to maintain them. Even the slightest cut in the tiles is enough to reduce the stealth capabilities of the fighter drastically. Thus, critical care and attention to this aspect required intensive care which was often hard to provide due to the high costs and time structures involved.
The F-117A Nighthawk was used in a variety of missions. However, its main debut was perhaps the Gulf War where it achieved its first monumental assignment. The fighter was a very good addition to the fleet and at the time of operation Desert Storm flew approximately 1300 sorties (FAS.org). They were categorized as one of most efficient bombing machines available at the time because they struck around 1600 targets, both due to their excessive use and their stealth abilities. Because of their prevailing success rate of 80, they were one of the very few aircrafts allowed to operate in bombing missions inside Iraqs Capital, Baghdad (FAS.org).
However, the story took an unusual twist in later years. Since the aircraft was being employed in all forms of combat, the United States decided to use the same tactic with the Kosovo conflict in 1999. However, this was met with a very monumental attack on one of the F-117As. At that time, it was not conceived that the fighter plane could be targeted given its enormous strength and stealth abilities. Also, its past history had reflected the same idea. However, one customized Surface to air missile (SA-3 Goa) was used against the aircraft which hit with pin point accuracy. It was noted that these newly developed weapons were capable of detecting the aircraft for a short moment of time by wavering the wavelength at unusually long levels (FAS.org). This meant that the stealth capabilities of the F-117A had been compromised since within no time, other countries would develop similar technologies. This was perhaps the dawn of the age of the retirement of the aircraft. This was particularly because after the downing of the first F-117A, the entire wreckage was never recovered. It has been widely cited that soviet intervention led to a deep analysis of the technology used in the development of the aircraft. This also meant that similar products would be launched by rival countries and the competitive advantage of the Nighthawk would be lost. Thus, began the spiral to try and wind the product up and develop a new one in light of the circumstances.
Even so, many critics still believe that the aircraft should not have been abandoned the way it was. They cite the fact that this is a conspiracy against all other fighter jets since the top elite of the USAF want to preserve the F-22A which is often termed as the Ultimate Fighter. They also cite the ability of the F-117A aircraft to carry payloads internally as an advantage. They claim that currently, even the F-22A carries payloads externally, under its wings. This reduces its stealth abilities but the fact is often disregarded by the USAF, which is surprising to many.
However, based on the evidence provided above and scientific research conducted in the analysis of the F-117A fighter, it is clear that the technology used at the time was state of the art. However, with the improvement of computers and technology, the usage of the F117-A was becoming redundant day by day. Its moment of retirement was near as it could not compete with newer developed aircrafts who were not only using the same basis of technology (Stealth) but also more efficiently. This is not to say that the F-117A was not an effective machine. In light of the time it was used in, it was operationally effective to a great deal. However, now, with bombers such as the F-22 which can reach stealth levels comparable to the revered B-2 stealth Bomber, the F-117A had to be retired. The F-22, often held as the successor to the F-117 is regarded as the new age of stealth technology. Not only can it fly at supersonic speeds without compromising on its stealth, it can also carry greater payloads and requires far lesser maintenance requirements for its RAMs, making it a good substitute to the F-117A.
To say that the F-117A has been retired would not be entirely correct. Without doubt they have been decommissioned from active service but they are still being stored in Tonopah, Nevada. Their wings and tails have been removed but they have been kept in a situation where they can be actively called to duty in a moment of crisis (Air Force- Technology.com).
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