Stealth Technology is the technology in which a plane or other vehicle is made to be virtually undetectable to radars and radar signals. How Radar Signals Are Blocked Using Stealth Technology Radar signals that are sent towards an aircraft that has stealth features can cause radar signals that are sent out by a radar unit by having the signals hit a part or all of the aircraft and what happens to those signals is that they either pass right through the aircraft or they are reflected towards another direction and this is caused because of the Radar Absorbent Material (RAM) and in this way the aircraft can be virtually ndetectable to radar.
The Development of Stealth Technology This Technology was cloaked in a veil of secrecy for almost two decades, but this entirely new family of aircraft has recently been announced to the public but the United States Department of Defence. These aircraft are virtually undetectable to radar, these new aircraft are the first examples of ” law observable, or stealth technology. Because radar in the primary means by wich aircraft are detected and tracked, it has become very important to the military service to make aircraft as invisible to radar as possible.
By building aircraft in certain ways or out or out of certain materials like exotic plastics, it is possible to control the direction or deduce the amount of radar energy they reflect. This prevents energy radar systems from spotting or tracking ” stealth” aircraft and from using weapons like anti-aircraft missiles to destroy them. There were attempts to build an aircraft that was ”stealthy ”with a low observables ” pair to the revelation of the new ”stealth” aircraft family.
Among these aircraft was a special lockhead U-2 reconnaissance aircraft painted with a coat of radar-absorbent aterial. Lockhead’s famous SR-71 , wich was the first aircraft to build from scratch that had a reduced radar return were the two highly classified Lockheed “Have Blue” prototypes. These aircraft were equipped with flat surfaces that reflected radar energy away from the radar’s receiver, this reducing the chances of detection. An operational descendant of the “Have Blue” aircraft has become well known as the Lockheed F-117.
This fighter- bomber has proved to be very successful in actual combat. The Northrop B-2 intercontinental range bomber is the latest “stealth” aircraft to be made public. It is built primarily of plastic-like composite materials, the B-2 avoids radar detection by absorbing radar energy or by allowing it to pass through with out being reflected. A “stealthy” fighter, the U. S. Air Forces Lockheed F-22, is also presently under development and may be in production at the end of this century.
“Stealth” is expected to become an integral part of all U. S. military aircraft designs from now on. Radar Reduction Because the advantages of “stealth” technology outweigh the disadvantages, these are considered nessecary evils, when a “stealth” aircraft is built. Increased empty weights esulted from the addition of external radar absorbent coating (RAM). From the engines, that are buried inside the structure of the aircraft. Which are put there to reduce the amount of heat they generate and from exotic and sophisticated engine exhaust nozzles that also help reduce heat generation.
Finally a full complement of heavy and space-consuming electronic countermeasures equipment which is a part of the aircraft’s defenses adds to it’s weight. All of these add weight that otherwise would not be an encumbrance, and weight equates to penalties in speed, range, and altitude performance. Another problem with incorporating “stealth” technology into an aircraft is a wing shape that does not provide the optimum amount of lift. The resulting increase in drag reduces flight performance. “Stealth” shapes, such as the faceting found on the Lockheed’s F-117 stealth fighter, also tends to be aerodynamically destabilizing.
This is brought under control only through the use of highly sophisticated computers that serve to electronically balance the aircraft while it is in flight through it’s autopilot and control system. Because range is reduced by many of the “stealths” physical constraints, “stealth” ircraft sometimes need to be bigger than the designers of the craft would like in order to carry sufficient fuel. “Stealth” aircraft can’t be equipped with external fuel tanks because doing this would increase the aircrafts radar reflectivity.
All the external protusions such as the eder of the landing gear doors, must be perfectly matched to prevent radar energy from being reflected. Because of this the detail work entailed in the design and construction of a “stealth” aircraft is much more exacting than in conventional aircraft. Even the smallest oversight in panel matching can make any “stealth” aircraft vulnerable o radar. Such exacting requirements increase engineering, manufacturing, and maintenance costs of the “stealth” aircraft so that they are several times as expensive as conventional or regular aircraft.
The Lockheed F-117A Stealth Fighter The Lockheed F-117A was developed under a veil of utmost security to project its advanced technology. The F-117A was the first operational military aircraft designed to be equipped with “low observable” or “stealth” features. Lockheed engineers have created an aircraft design that cuts off the amount of radar energy sent back to a radar receiver. As a result, the F-117 is strangely shaped with many flat surfaces, or facets, and has proved to be very difficult to be seen or tracked on radar.
Used on several occurrences, the F-117 has proven that its technology works; enemy attempts to track and destroy F-117s have been unsuccessful to date. Just over 50 F-117s are in service. The F-117 Stealth Fighter Lockheed’s success during the late 1970’s with their two “Have Blue” prototype aircraft proved beyond doubt that the faceting surface design pioneered by these aircraft could noticeably reduce an aircraft’s radar cross section. By the early 1980’s, the prototypes of what would come to be known as the F-117 Stealth Fighter were being flight tested.
The F-117 is a twin engine design of conventional construction. However, it differs from other, more conventional aircraft in having faceted surfaces, a highly swept wing, and special sensors for night flying and accurate weapon delivery. It also has a strange nozzle design. It’s extraordinary capabilities lie in it’s strange design, which was computer generated and optimized to reflect radar energy away from the radar’s reciever unit, not toward it. In addition to it’s latplate surfaces, the F-117 also incorporates an external covering of radar absorbent material, making it even more difficult to spot on radar.
The F-117 proved itself during the Gulf War in the Middle East. During combat over Iraq, not one F-117 was lost or even hit to the intense anti-aircraft defences. Equally important, the F-117 was found to have an extraordinary accurate weapon delivery capability, at times of delivering bombs within an inch or two of the intended bullseye. The B-2 Stealth Bomber During The early 1980’s, the U. S. Air Force once again called for the evelopment of an intercontinental bomber to replace the aging Boeing B-52 Bomber.
The new bomber would incorporate the latest in “stealth” technology, giving it the ability to operate in highly radar saturated areas without being detected. To attain the stealth goal, many engineering specialties had to be brought into play, including the use of composite construction materials, which are correspondent to conventional plastics. The use of composites in an aircraft as large as the new bomber set new designed designed precedents; previously, composites had rarely been used in the principal element of an ircraft’s structure.
Other characteristics addressed included its infrared structure, its noisiness and its visibility. The Northrop company was chosen to build the new bomber, officially named the B-2 by the Air Force. Because of its innate stealth features, Northrop chose the tailless flying wing configuration for the new bomber’s design. With its parallel edge shaping, it buried exhaust, its use of radar absorbent materials, and it’s use of internal bulk radar absorbers, the B-2 is currently the most advanced stealth aircraft in the world. The Northrop B-2 Spirit
Northrop’s B-2 bomber illustrates the latest in “stealth” technology and has a very low radar cross section, making it all but invisible to radar energy. With a small front area, advanced construction techniques and materials, and the latest in electric countermeasures, the B-2 is almost induitably the world’s most difficult radar target. I t can carry thermonuclear weapons over long distances and was built to attack intercontinental strategic targets. The high cost of the bomber and the brake up of its former target- the Soviet Union- mean that just 20 B-2’s are being built for the U. S. Air Force instead of the 133 originally intended.
Detail Shaping Even if total external shape is optimized to provide excellent “stealth” values it will be of little consequence unless attention is paid to small details such as surface gaps, compartment doors, engine and system inlets, windows, and antennas. The most perfect “stealth” design would also be quickly, compromised if anything such as fuel tanks, rocket launcher, air-to-air missiles were mounted externally. For this reason, all fuel and weapons must be carried internally in special bays and all door and access panels must eal very tightly.
Weapons bays doors, which open in flight to release weapons, must operate rapidly and be designed to reduce the amount of radar reflections. Even the windshield that usually consist of multiple acrylic plastic layers with gold or indium oxide coatings in between, are not overlooked. The coatings reduce radar returns from the cockpit without significantly effecting the optical properties of the clear acrylic. Engine inlets, which channel air into the engine compartments for combustion, are given special consideration in “stealth” aircrafts.
Because jet engine turbine blades can reflect radar energy, the inlet is designed to reduce chances of this happening. Duct compartments often incorporate radar-absorbing materials and an s-shaped duct, for instance, can remove the engine from direct line-of-sight, thus reducing the amount of radar energy reflected back. All of these modifications, however hurt the planes performance, adding weight, affecting aerodynamics, and altering the structure of the aircraft. The advantages of stealth technology must always be weighed against its disadvantages.
Conclusion The advantages of stealth technology are that it allows aircraft to virtually be undetected by radar so they can deeply penetrate and attack enemy defenses, bases, or territory. The disadvantages of stealth technology are that if an aircraft is being equipped with stealth features it has to be accuratley matched all over the external body of the aircraft. Even if there was a slight difference in this being matched it could be disasterous to the aircrafts out come in a war because it could be tracked and destroyed because of radar signals.
