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This document discusses stealth technology and how it applies to air assets. It begins by providing background on how stealth became mainstream after the 1991 Gulf War. It then defines stealth as using techniques to make vehicles less visible to radar, infrared, sonar and other detection methods. The key is minimizing signatures and signals to prevent detection. For air vehicles, radar and infrared signatures are most important to reduce. The document discusses the basic principles of stealth technology and how it aims to reduce radar cross-section and other signatures. It provides a brief history of stealth's development and defines the different types of signatures stealth techniques aim to minimize.
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- 1. 1 1.INTRODUCTION "Stealth", a buzzword common in defense circles since the early 80s, only became a mainstream reference in the nineties, after the second Persian Gulf War in 1991.Night- enhanced images of the otherworldly-shapedF-117s taking off in the night and striking high- value targets with scarcely believable precision and seeming invulnerability to thick air defense were widely televised and etched in the memories of TV viewers worldwide. The subsequent exposure of stealth aircraft and their participation in numerous air operations in the 90s, in combination with the loss of at least one F-117 in Kosovo, has peeled off some of the mythical cloak surrounding stealth. However, a lot of misconceptions about the abilities and limitations of this technology still remain, even amongst people in posts of high professional responsibility. It is therefore useful to take a broad look at how stealth works, what it can and what it cannot do. This report will examine strictly the application of stealth in air assets. Different technologies and strategies for stealth are the province of land, naval and underwater forces. From the late years of World War II to today's computer enabled design changes, stealth has been a major factor in the improvement of reconnaissance and attack aircraft. The term "stealth", is thought to have been coined in 1966 by Charles E. "Chuck" Myers, combat pilot and later an exec at Lockheed. Ben Rich, the leader of the Lockheed team that designed the F-117, has stated: "A stealth aircraft has to be stealthy in six disciplines: radar, infrared, visual, acoustic, smoke and contrail. If you don't do that, you flunk the course." That said, not all disciplines are equally important when discussing any given platform category. Underwater warfare will naturally hand dominance to the acoustic spectrum (though on acoustic sensors can and do exist). Land combat will emphasize visual, infra-red and acoustic signatures. Radar and (to a lesser extent) infrared bands dominate the scene of airspace surveillance, and so they have to be given higher priority when thinking the applications in air warfare.
- 2. 2 Before discussing the various techniques of reducing the radar and infrared signature, it is useful to understand the principles of radar reflectivity and how they can be exploited when one starts thinking about aiming for stealth in earnest.
- 3. 3 2.STEALTH TECHNOLOGY “Oh divine art of subtlety and secrecy! Through you we learn to be invisible, through you inaudible and hence we can hold the enemy’s fate in our hands.” Sun Tzu – Chinese General, The Art of War, c.490 B.C. Stealth technology also known as LO technology (low observable technology) is a sub discipline of military electronic countermeasures which covers a range of techniques used with aircraft, ships, submarines, and missiles, in order to make them less visible (ideally invisible) to radar, infrared, sonar and other detection methods. 2.1 Stealth principles Stealth technology (or LO for "Low Observability") is not a single technology. It is a combination of technologies that attempt to greatly reduce the distances at which a vehicle can be detected; in particular radar cross section reductions, but also acoustic, thermal, and other aspects. Stealth technology aims at minimizing signatures and signals, and prevent/delay detection and identification, thus increasing the efficiency of the vehicles own countermeasures and sensors. Ben Rich, the leader of the Lockheed team that designed the F117, pretty much sums up stealth technology when he say: “A stealth aircraft has to be stealthy in six disciplines: radar, infrared, visual, acoustic, smoke and contrail. If you don’t do that, you flunk the course.” However, not all disciplines are equally important when discussing any given platform category. Underwater warfare will naturally hand dominance to the acoustic spectrum. However, land combat will emphasize visual, infrared and acoustic signatures. Radar and infrared bands dominate the scene of airspace surveillance. 2.2 The term “Signature” of a Vehicle Signature - Any unique indicator of the presence of certain materiel or troops; especially the characteristic electronic emissions given off by a certain type of vehicle, radar, radio, or unit.
- 4. 4 Thus Signature can be concluded as any activity or radiation or the characteristic of the body that helps to revile its presence at a particular point. All the detection methods used that be in military and civil systems are by detecting the signature of the body. This signature is called by different names in different contexts. Radar Signature is called Radar Cross Section or RCS and so on. Thus signature can be rightly called as observability of an object and stealth vehicles can be called as low-observable vehicles or low-signature vehicles. 2.3 What’s the need for Quantum Stealth? It’s a matter of fact that the rapid development of stealth technology occurred due to the pronounced improvement of the detection techniques like radar’s as they were the most commonly used detection methods in the 1930’s & 40’s. There are some key strategies that triggered the development of the Stealth technology like the use of Radar Aided-Anti aircraft systems and the use of Sonar’s for detecting the Submarines by the Ships etc. Thus the rapid development was the need of time to reduce causalities. And that still remains so. As Stealth technologies touching new heights day by day in the other side Anti- Stealth technologies are also in full momentum to outdate the Stealth technologies. Thus stating the need of Quantum stealth technology.
- 5. 5 Fig 2.1 BASIC PRINCIPLES 2.4 History of Stealth In the late 1930’s and 1940’s Radar technology was commonly used for detecting aircrafts. Since radar technology was developed during the Second World War, it should not be surprising to learn that the first attempts at stealth technology occurred during this period also. It might be surprising to learn, however, that it was the Germans, not the Allies, who worked on the project. The Germans were responding to the success the Allies were having with the early radar sets. Not only was their radar very effective at spotting incoming enemy bombers, but it was also very important in the battle for the Atlantic. The Germans developed a radar absorbing paint. While this ferrite-based paint was much too heavy for aircraft, it could be used on submarines After much effort USA was successful in building an aircraft that could evade the enemy RADAR’s called the F-117A nicknamed as the “Nighthawk”, developed by Lockheed Martin in 1983.
- 6. 6 3. SIGNATURES Signature - Any unique indicator of the presence of certain materiel or troops; especially the characteristic electronic emissions given off by a certain type of vehicle, radar, radio, or unit. Thus Signature can be concluded as any activity or radiation or the characteristic of the body that helps to revile its presence at a particular point. All the detection methods used that be in military and civil systems are by dectecting the signature of the body. This signature is called by different names in different contexts. Radar Signature is called Radar Cross Section or RCS and so on. Thus signature can be rightly called as observability of an object and stealth vehicles can be called as low-observable vehicles or low-signature vehicles. TYPES OF SIGNATURES: • RCS: - Aircrafts, Missiles, Ships, Land Vehicles. • Infrared signature:- Aircrafts, Missiles, Ships, Land Vehicles, Submarines. • Acoustic Signature: - Predominantly for Submarines (SONAR), Ships, Aircrafts etc. • Visible Signature: - Predominantly for Land Vehicles, Aircrafts, and Ships. • Laser Cross Section:-Aircrafts, Missiles, Ships, Land Vehicles. • Magnetic Signature: - Submarines, Ships. Fig 3.1 RADAR SIGNATURE Fig 3.2 MAGNETIC SIGNATURE
- 7. 7 4. RADAR RADAR is abbreviated as Radio detection and ranging which is one of the most useful technologies in the present day warfare. This is used to launch the missiles based on the target and also counter attack the missile launched by other countries. Radar basically works on two major principles. 4.1. ECHO Echo can be considered as a wave bouncing off a surface and coming back to the source. This Principle can be applied for all types of waves starting from sound waves to light waves. the time for the reception of the transmitted signal to reach the transmitter cum receiver can be effectively used to calculate the distance of the target from the transmitter. 4.2. The Doppler Shift This being the second principle of the radar. This effect is more commonly felt for sound. The sound that you hear as a vehicle is approaching you is at a higher pitch or a higher frequency than the sound you hear when the vehicle is moving away from you. This property when applied to radar can be used to determine the speed of the object. The frequency of the reflected wave can be the same, greater or lower than the transmitted radio wave. if the reflected wave frequency is less then this means that the target is moving away from the transmitter and if higher then moving close to the transmitter and if constant then the target is not moving like a helicopter hovering at a point. This can be used to predict the speeds of the target too. 4.3 Why Radio waves and not sounds waves? Although the above said principles are applicable to sound waves radio waves are used for detection and ranging due to the following reasons. The speeds of the radio waves are comparable with that of light and are much higher than that of sound. Sound waves cannot travel as far as light in the atmosphere without significant attenuation. And finally, electromagnetic echo is much easier to detect than a sound echo.
- 8. 8 4.4 Radar Cross Section (RCS) Radar cross section is the measure of a target's ability to reflect radar signals in the direction of the radar receiver, i.e. it is a measure of the ratio of backscatter power per steradian (unit solid angle) in the direction of the radar (from the target) to the power density that is intercepted by the target. The RCS of a target can be viewed as a comparison of the strength of the reflected signal from a target to the reflected signal from a perfectly smooth sphere of cross sectional area of 1 m2 as shown in Figure. Fig 4.1 Various RCS
- 10. 10 5. RADAR STEALTH There are two broad aspects of RCS minimization techniques. One falls under the effort to restructure the frame, and covers the geometric design considerations that are taken into account when aiming for a low RCS. The other principle is referred to as “radar absorbent materials” and is concerned with the materials that help to reduce the reflectivity of the airframe, as well as the structures that will support these materials and integrate them into the airframe often referred to as “Radar-absorbent structures”. These two axes are of course not taken in isolation during the design; trade-offs often have to be made between them. 5.1 Vehicle Shape The stealth designer's mission starts with the same words as the physician's Hippocratic Oath: "First, does no harm." The prime most concern being that of the aircraft's The possibility of designing aircraft in such a manner as to reduce their radar cross-section was recognized in the late 1930s, when the first radar tracking systems were employed, and it has been known since at least the 1960s that aircraft shape makes a significant difference in detectability. The Avro Vulcan, a British bomber of the 1960s, had a remarkably small appearance on radar despite its large size, and occasionally disappeared from radar screens entirely. It is now known that it had a fortuitously stealthy shape apart from the vertical element of the tail. On the other hand, the Tupolev 95 Russian long range bomber (NATO reporting name 'Bear') appeared especially well on radar. It is now known that propellers and jet turbine blades produce a bright radar image; the Bear had four pairs of large (5.6 meter diameter) contra-rotating propellers. Another important factor is the internal construction. Behind the skin of some aircraft are structures known as re-entrant triangles. Radar waves penetrating the skin of the aircraft get trapped in these structures, bouncing off the internal faces and losing energy. This approach was first used on the F-117. The most efficient way to reflect radar waves back to the transmitting radar is with orthogonal metal plates, forming a corner reflector consisting of either a dihedral (two plates) or a trihedral (three orthogonal plates). This configuration occurs in the tail of a conventional aircraft, where the vertical and horizontal components of the tail are set at right angles. Stealth
- 11. 11 aircraft such as the F-117 use a different arrangement, tilting the tail surfaces to reduce corner reflections formed between them. A more radical approach is to eliminate the tail completely, as in the B-2 Spirit. Fig 5.1 Corner Reflector In addition to altering the tail, stealth design must bury the engines within the wing or fuselage, or in some cases where stealth is applied to an existing aircraft, install baffles in the air intakes, so that the turbine blades are not visible to radar. A stealthy shape must be devoid of complex bumps or protrusions of any kind; meaning those weapons, fuel tanks, and other stores must not be carried externally. Any stealthy vehicle becomes non stealthy when a door or hatch is opened. Stealth airframes sometimes display distinctive serrations on some exposed edges, such as the engine ports. The YF-23 has such serrations on the exhaust ports. This is another example in the use of re-entrant triangles and platform alignment, this time on the external airframe. Ships have also adopted similar techniques. The Visby corvette was the first stealth ship to enter service, though the earlier Arleigh Burke class destroyer incorporated some signature reduction features. In designing a ship with reduced radar signature, the main concerns are radar beams originating near or slightly above the horizon (as seen from the ship) coming from distant patrol aircraft, other ships or sea-skimming anti ship missiles with active radar seekers. Therefore, the shape of the ship avoids vertical surfaces, which would perfectly reflect any such beams directly back to the emitter. Retro-reflective right angles are eliminated to avoid causing the cat's eye effect. A stealthy ship shape can be achieved by constructing the hull and superstructure with a series of slightly protruding and retruding surfaces. This design
- 12. 12 was developed by several German shipyards, and is thus extensively applied on ships of the German Navy. Fig 5.2 Radar scattering due to shaping Fig 5.3 Serrated Shape for RCS Reduction Measures 5.2 Coatings and Absorbers 5.2. a. RAMs (Radar Absorbing Materials):
- 13. 13 Radar-absorbing materials (RAMs) are used to dissipate the energy of the radar wave so to prevent the reception of a reflected signal by an antenna. Usually, the dissipation process converts the radio frequency (RF) energy to a negligible quantity of heat. RAMs are one of four ways of reducing the radar cross-section of an object, which is a measure of the reflection of radar waves by an object. A larger radar cross-section (RCS) of an object corresponds to a longer detection range and a higher signal-to-noise ratio for the observing radar operator. A 747 would have a huge RCS, whereas a bumblebee would have an insignificant RCS. Other ways of reducing RCS include passive cancellation, incorporating an echo source which by design cancels another echo source for a certain frequency and angle, active cancellation, incorporating a sensor and emitter which cooperate to radiate waves which interfere with incident radar waves, and by geometric shaping and design modifications. Only the last will be discussed, as the former two are rather impractical and are less dependent on material or process properties. Dielectric and magnetic RAMs are the two main types (along with various combinations of these) of RAMs in current operational use; these will be explored in further detail as we go along. Types of RAMs : 1. IRON BALL PAINT 2. FOAM ABSORBER 3. JAUMANN ABSORBER Carbon nanotubes (CNTs) are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1, significantly larger than for any other material. These cylindrical carbon molecules have unusual properties, which are valuable for nanotechnology, electronics, optics and other fields of materials science and technology. One of the more recently researched properties of multi- walled carbon nanotubes (MWNTs) is their wave absorption characteristics, specifically microwave absorption. Interest in this research is due to the current military push for radar
- 14. 14 absorbing materials (RAM) to better the stealth characteristics of aircraft and other military vehicles. There has been some research on filling MWNTs with metals, such as Fe, Ni, Co, etc., to increase the absorption effectiveness of MWNTs in the microwave regime. Thus far, this research has shown improvements in both maximum absorption and bandwidth of adequate absorption. FIG 5.4 RAM FIG 5.5 CNT in RAM
- 15. 15 6. ACOUSTICS STEALTH Acoustics means Sound and Acoustic signature is used to describe a combination of acoustic emissions of ships and submarines. Although Acoustic Signature are found in for land and ariel units acoustic signature turns out to be the key method of dectection for Naval field rather than the other two. 6.1 SONAR (SOund Navigation And Ranging) Sonar is very important part of anti submarine warfare. The sonar is a device for detecting and locating objects submerged in water by means of the sound waves they reflect or produce. It means that the active sonar wasn’t used in fight against submarines. The first active sonar was constructed in 1918, in the Admiralty Experimental Station (UK). On the first testing the sonar found merged submarine on distance of a few hundred meters. 6.1.a. Hydro Acoustics Sound is mechanical oscillating. Spreading of the sound is possible because of elastic connection between molecules. Molecules in liquids are closer one to another than in the air. Because of that the sound spreads faster in the water than in the air. Speed of the sound in the water is 4.4 times faster than in the air. Exact speed of the sound in the water is 1438 m/s, when temperature of the water is 8 degrees Celsius. Speed and direction of the sound wave spreading depend about temperature, salinity and depth of the water. The speed with which sound is transmitted is a characteristic of the material in question, proportional to the modulus or stiffness of the material and inversely proportional to its density. For example, the speed of sound in sea water can be calculated as follows: Where, C = Speed of sound in sea water, approx. 57,735 in/sec, or 4,800 ft/sec, disregarding effects of
- 16. 16 temperature, salinity, and pressure.~ 1450 m/s K = Bulk modulus of sea water = 300,000 psi. ρ = Density of sea water, based on a specific weight of 64 lbs./cu.ft. = 9 x 10-5 slugs/cu.in. 6.1.b. Sonar Properties The first practical sonar units have been constructed between WW1 and WW2. The best working frequency was 20 kHz, pulse power was 50 W. Range was 1000 to 1500 meters (good working conditions) or 500 to 700 meters (bad working conditions). In WW2 there are two types of sonar, projection type and panoramic type. 6.1.c. Sonar absorbers Making an efficient, broadbanded sonar absorber presents a number of technical challenges. Most absorptive materials do not have the requisite impedance, and rigid materials are not lousy enough. In some cases, scattering can be used to enhance absorption, but this is not always practicable. Even more difficult are the effects of wavelength: absorbers designed for high frequencies are ineffective at low frequencies. Finally, whatever system is used, it must have good hydrostatic strength so that it may be used deep in the sea. The most promising development in this area is a new family of composite materials employing rigid syntactic foam in combination with a variety of fillers and ingredients. The addition of suitable additives to the syntactic system can provide a controlled amount of scattering or absorption. Reducing the elastic modulus of the resin binder to create more “rubbery” foam will introduce acoustic loss. A truly broadbanded sonar absorber with good hydrostatic strength can be made by dispersing suitably-sized elastomeric particles in a syntactic foam matrix. Using these principles, successful underwater sound absorbers have been made for a variety of military and civilian applications. Syntactic foam is a lightweight, high strength composite material frequently used in the sea for floats and buoys, to support instruments, as submarine void filler, for encapsulating hydrophones, and so on.
- 17. 17 Fig6.1 Example of Sonar Absorbing Material
- 18. 18 7. INFRARED STEALTH Infrared radiations are emitted by all matter above absolute zero temperature. Hot materials, such as engine exhaust gasses or wing surfaces heated by friction with the air, emit more infrared radiations than cooler material. Heat seeking missiles and other weapons zero in on the infrared glow of hot aircraft parts. Infrared stealth therefore requires that aircraft parts and emissions, particularly those associated with engines must be kept as cool as possible. Embedding jet engines inside the wings is one basic design step towards infrared stealth. Other measures include extra shielding of hotter parts, mixing of cooler air with hot exhausts before emission, splitting the exhaust stream by passing it through the parallel baffles so that it mixes cooler air very quickly, directing of hot exhaust upwards, away from ground observers. For aircraft detection, IR seekers look for contrasts between hot parts on the airframe such as jet pipes and surfaces subject to kinetic heating, and the background radiation. In designing IR detectors several things have to be considered: the range of wavelengths emitted by the target, the likely wavelength of the most intense radiation, the ways these wavelengths are affected by the atmosphere; and because the maximum contrast is desired, the character of the likely background radiation. Many IR devices operate in the 8-13 micron band since this is the most IR-transparent band in the atmosphere. In engine exhausts, carbon dioxide produces most of the IR signature at 4.2 microns, so modern IR sensors can 'see' attwo different wavelengths, (medium: 3-5 microns and long:8-14 microns) to provide good target discrimination. The engine exhausts are the primary battlefield in the war against infrared detection. There are many types of infrared sensor in service, and their different capabilities are sometimes confused. The basic fact is that the atmosphere absorbs infrared energy. At a range of a few miles, a small infrared sensor can receive enough energy to produce TV-type image of the scene; at greater ranges, this capability is much diminished. Most medium-to-long-range systems do not detect the Infrared emissions from the aircraft itself, but the radiation from the hot air and water vapour emitted by its engines the radiated IR energy is proportional to the fourth power of absolute temperature. With engine turbine entry temperatures (TETs) currently at around1, 900K and rising, the back end of a military aircraft is the greatest source of IR radiation. With afterburner on, it becomes more so. Moderate stagnation temperatures are inevitable on leading
- 19. 19 edges of a fighter's airframe due to kinetic heating at high Mach numbers. As the stealthiest of fighter’s increases so their missiles' exhaust plumes play a greater role in early detection. Lower visibility plumes will minimize detection of both launch platform and missile. The key to degrading the performance of IRST systems is to ensure that the exhaust dissipates as quickly as possible after leaving the aircraft. For example, the engines can be fitted with flow mixers to blend the cold bypass air with the hot air that passes through the combustor and the turbine. The exhausts geometry can be adapted to a wide and flat shape rather than the traditional round, increasing the mixing rate (but probably reducing thrust efficiency). Furthermore, the interaction between the exhaust stream and the airflow over the aircraft can be engineered to create an additional vortex which further promotes mixing. There are several other methods to reduce the IR signature: 1. Have the ability to super cruise (cruise at supersonic speeds without afterburning) to restrict the temperature of the nozzle. Moreover, super cruising allows the pilot to engage on his terms, increases weapons' envelopes, minimizes exposure to SAM threats and not only stretches combat radius but forces an adversary to expend his own fuel in order to get his aircraft to an energy states where he can engage it. 2. Use a high bypass ratio (BPR) engine to mix in cold air to reduce exhaust temperature. That said, a bypass ratio greater than about 0.4 conflicts with the requirement of the high dry thrust to achieve super cruise. 3. Increase cooling of the outer skin of the engine bay or insulation to reduce temperature of the airframe skin.
- 20. 20 Fig 7.1 IR Signatures
- 21. 21 8. PLASMA STEALTH Plasma Stealth can be considered as a specific Stealth method employed for Ariel stealth. Couple of things to keep in mind: plasma is ionized gas particles. Therefore, plasma flow is a flow of ionized gas particles. Ion is an electrically charged particle or group of atoms. Plasma cloud is a quasineutral (total electrical charge is zero) collection of free charged particles. Plasma absorbs radio waves, so it is theoretically possible to diminish the RADAR reflectivity of a no stealthy aircraft by generating plasma at the nose and leading edges of the aircraft. A device for generating plasma is called plasmatron. This device generates the so-called low- temperature plasma. It is not known whether the plasma stealth system developed by the Russians employs a plasma laser or some other method for creating a plasma field. In plasma stealth, the aircraft injects a stream in front of the aircraft. The plasma will cover the entire body of the fighter will cover the entire body of the fighter and will absorb most of the electromagnetic energy of the radar waves, thus making the aircraft difficult to detect. Xenon nuclear poison isotopes when successfully suspended in generated plasma layers or doped into vehicle hulls, may be utilized in order for a reduction in radar cross-section. If tunable this could shield against HMP/EMP and HERF weaponry or act as optical radiation pressure actuators. It is still under development.
- 22. 22 9. INDIA’s STEP TOWARDS STEALTH The Indian Armed Forces are also making serious attempts to bring home the stealth technology. The two aircrafts with stealth are: HAL Light Combat Helicopter (LCH): It is a multirole combat helicopter being developed in India by Hindustan Aeronautics Limited (HAL) for use by the Indian Air Force and the Indian Army. According to reports, the LCH features a digital camouflage system. The first prototype of LCH completed its first ground run on 4 February 2010. HAL has a firm order to deliver 65 LCH to the IAF and 114 to the Army. DRDO AURA: It is an autonomous unmanned combat air vehicle (UCAV), being developed by the DRDO for the Indian Air Force. The design work on the UCAV is to be carried out by Aeronautical Development Agency (ADA). Details of the project are classified. The AURA will be stealth UCAV, capable of releasing missiles, bombs and precision-guided munitions. The programme is in its project definition stage. The design is in line with what former DRDO chief controller for Aeronautics said in 2007, that India's combat drone would be a stealthy flying-wing concept aircraft with internal weapons and a turbofan engine. The UCAV's design is similar to Northrop Grumman's B-2 Spirit. Fig 9.1 LAC
- 23. 23 10. ADVANTAGES OF STEALTH TECHNOLOGY 1. A smaller number of stealth vehicles may replace fleet of conventional attacks vehicles with the same or increased combat efficiency. Possibly resulting in longer term savings in the military budget. 2. A Stealth vehicles strike capability may deter potential enemies from taking action and keep them in constant fear of strikes, since they can never know if the attack vehicles are already underway. 3. The production of a stealth combat vehicles design may force an opponent to pursue the same aim, possibly resulting in significant weakening of the economically inferior party. 4. Stationing stealth vehicles in a friendly country is a powerful diplomatic gesture as stealth vehicles incorporate high technology and military secrets. 5. Decreasing causality rates of the pilots and crew members. 6. weapons and/or platforms, the base is caught virtually napping and the attack is detected so perilously close that the enemy Has no time to get anything in the air but instead can only rely on his ground-based terminal defenses . This can mean the difference between the base suffering little or no damage and being virtually obliterated.
- 24. 24 11. DISADVANTAGES OF STEALTH TECHNOLOGY 1. Quantum Stealth has its own disadvantages like other technologies. Stealth aircraft cannot fly as fast or is not maneuverable like conventional aircraft. The F-22 and the aircraft of its category proved this wrong up to an extent. Though the F-22 may be fast or maneuverable or fast, it can't go beyond Mach 2 and cannot make turns like the Su-37. 2. Another serious disadvantage with the stealth aircraft is the reduced amount of payload it can carry. As most of the payload is carried internally in a stealth aircraft to reduce the radar signature, weapons can only occupy a less amount of space internally. On the other hand a conventional aircraft can carry much more payload than any stealth aircraft of its class. 3. Whatever may be the disadvantage a stealth vehicle can have, the biggest of all disadvantages that it faces is its sheer cost. Stealth aircraft literally costs its weight in gold. Fighters in service and in development for the USAF like the B-2 ($2 billion), F-117 ($70 million) and the F-22 ($100 million) are the costliest planes in the world. After the cold war, the number of B-2 bombers was reduced sharply because of its staggering price tag and maintenance charges.
- 25. 25 12. FUTURE SCOPE Quantum Stealth technology is clearly the future of air combat. In the future, as air defense systems grow more accurate and deadly, stealth technology can be a factor for a decisive by a country over the other. In the future, stealth technology will not only be incorporated in fighters and bombers but also in ships, helicopters, tanks and transport planes. These are evident from the RAH-66 "Comanche" and the Sea Shadow stealth ship, Sea Shadow (IX-529) is an experimental stealth ship built by Lockheed for the United States Navy to determine how a low radar profile might be achieved and to test high stability full configurations which have been used in oceanographic ships. Ever since the Wright brothers flew the first powered flight, the advancements in this particular field of technology have seen staggering heights. Stealth technology is just one of the advancements that we have seen. In due course of time we can see many improvements in the field of military aviation which would one-day even make Quantum stealth technology obsolete. This is not a new idea , in fact several military fiction writers have already come up with the idea, in one particular instance having the aircraft continually modifying top and bottom like a magician's mirror box making the aircraft totally invisible.
- 26. 26 13. CONCLUSION The Detection and Stealth Technology has improved significantly more advanced in the last fifty years or so. This trend is likely to continue as these two oppose each other. Till date stealth aircraft have been used in several low and moderate intensity conflicts, including operation Desert Storm. Operation Allied Force and the 2003 invasion of Iraq .Killing of Osama Bin Laden in Abbottabad, Pakistan. In all cases they were employed to strike high value targets which were either out of range of conventional aircraft or which were too heavily defended for conventional aircraft to strike without a high risk of loss. In addition, because The stealth aircraft aren't going to be dodging surface to air missiles and anti-aircraft artillery over the target they can aim more carefully and thus are more likely to hit the high value targets early in the campaign (or even for it) ,Before other aircraft had the opportunity to degrade the opposing air defense. However, given the increasing prevalence of excellent Russian-built Surface -to-air missile (SAM) system on the open market, stealth aircraft are likely to be very important in a high intensity conflict in order to gain and maintain air supremacy. Stealth technology .in future, would be required for clearing the way for deeper strikes , which conventional aircraft would find very difficult .For example ,China license-builds a wide range of SAM systems in quantity and would be able to heavily defend important strategic and tactical targets in the event of some kind of conflict .Even if antiradiation weapons are used in an attempt to destroy the SAM radars of such systems, these SAMs are capable of shooting down weapons fired against them. The surprise of a stealth attack may become the only reasonable way of making a safe corridor for conventional bombers. It would then be possible for the less-stealth force with superior weaponry to suppress the remaining systems and gain air superiority. The development and the deployment of the Visby's- the first commissioned Stealth ships has raised new threats in the maritime boundaries. The sudden appearance of sea clutters on the radar at a region may be these ships. The plasma stealth technology raises new hopes of engineering brilliance. As plasma is said to absorb all electromagnetic radiation the development of a counter stealth technology to such a mechanism will be a strenuous task.
- 27. 27 Stealth is a revolutionary technology in that it has the potential to change the way air power is exercised. The applications that this technology has span the entire gamut of air operations. In offensive applications of air power stealth has the potential to reduce the vulnerability of aircraft. This has spin-offs in the reduction of support elements for strike packages and smaller strike packages. Air defense operations benefits from giving the interceptors an undetected approach to their targets. Special operations benefit from the ‘evasion of notice’ that stealth bestows upon them. This is particularly so in the case of special operations as these, by their very nature, are important but vulnerable operations. On the whole it can be seen that stealth bestows more advantages to offensive operations and the offensive use of air power than it does to defensive use of air power. The offence-defense balance is thus seen to shift towards the offence. This is particularly in case the adversarial sides have asymmetric stealth capability, but applies in case of symmetric stealth capability also. Almost all nations with a desire to maintain powerful military forces are pursuing stealth aircraft programs, either indigenously or in collaboration with other technologically more advanced countries. Access to stealth technology is likely to be the key deciding factor in the relative effectiveness of air forces in the twenty-first century. Well to conclude the current scenario appears something similar to the cold war both sides are accumulating weapons to counter each other and each side can be termed as "Stealth Technology" and the other as "Anti-Stealth Technology". It's an arm race except it isn't between specific countries. "It's a fight between Technologies".