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STEALTH FIGHTER. INTRODUCTION. Stealth technology referred as “VLO” ie “VERY LOW OBSERVABLE TECHNOLOGY” Fighter planes are made so they are harder to be detected by the radar and other devices The first combat use of stealth aircraft was in December 1989 during Operation Just Cause in Panama
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INTRODUCTION Stealth technology referred as “VLO” ie “VERY LOW OBSERVABLE TECHNOLOGY” Fighter planes are made so they are harder to be detected by the radar and other devices The first combat use of stealth aircraft was in December 1989 during Operation Just Cause in Panama Well known examples include the United States' F-117 Nighthawk (1980s-2008), the B-2 Spirit "Stealth Bomber," and the F-22 Raptor
HISTORY The first true "stealth" aircraft may have been the Horten Ho 229flying wing fighter-bomber, developed in Germany during the last years of WWII. SR 71 the first Stealth airplane launched. It is well known as 'black bird'.
STEALTH TECHNOLOGY The goal of stealth technology is to make an airplane invisible to radar There are two different ways to create invisibility: The airplane can be shaped so that any radar signals it reflects are reflected away from the radar equipment. The airplane can be covered in materials that absorb radar signals stealth aircraft has to be stealthy in six disciplines: radar, infrared, visual, acoustic, smoke and contrail.
RADAR stealth fighter coventional aircraft
SHAPING OF STEALTH The shape should be flat or rectilinear and at the same time oblique to the incoming waves Another method bounce back on a very limited number of directions, maybe only one or two a compact, smoothly blended external geometry to achieve a continuously varying curvature
RAM & RAS RAM Reffers to “RADAR ABSORBENT MATERIALS” Most such material consists of an active ingredient—a dielectric, such as carbon, or magnetic ferrites—which is moulded into a non-lossy dielectric matrix, usually a plastic of some kind. RAS reffers to “RADAR ABSORBENT STRUCTURE” To achieve a high degree of absorption over a wide bandwidth is to use “honeycomb “ structure
ACTIVE CANCELLATION Active cancellation is a theoretical military jamming system that involves the sampling of an incoming radar signal, analyzing it, then returning ths signal slightly out of phase, thus "cancelling" it out.
PLASMA STEALTH Plasma stealth is a proposed process that uses ionized gas (plasma) to reduce the radar cross se ction (RCS) of an aircraft. conductivity of the plasma allows it to interact strongly with the incoming radio wave, but the wave can be absorbed and converted into thermal energy rather than reflected. plasma might also be used to modify the reflected waves to confuse the opponent's radar system Absorption of EM RADIATION by plasma stealth
DETECTION BY INFRARED RADIATION Passive IR detection devices rely on the fact that every atom of matter, including clouds and rain, continuously sends out electromagnetic radiation at an IR wavelength which corresponds to its temperature. For aircraft detection, IR seekers look for contrasts between hot parts on the airframe In engine exhausts, carbon dioxide produces most of the IR signature at 4.2 microns IR sensors can 'see' at two different wavelengths, (medium: 3-5 microns and long:8-14 microns) to provide good target discrimination.
INFRARED STEALTH to degrading the performance of IRST systems is to ensure that the exhaust dissipates as quickly as possible after leaving the aircraft. Some of the techniques are follows 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 Interaction between the exhaust stream and the airflow over the aircraft can be engineered to create an additional vortex which further promotes mixing
OTH Radar (Over the Horizon Radar) Over-the-horizon radar is a design concept that increases radar's effective range over conventional radar It is claimed that the Australian JORN Jindalee Operational Radar Network can overcome certain stealth characteristics. It is claimed that the HF frequency used and the method of bouncing radar from ionosphere overcomes the stealth characteristics of the F-117A.
USE OF STEALTH AIRCRAFT stealth aircraft have been used in conflicts, including Operation Desert Storm, Operation Allied Force and the 2003 invasion of Iraq. employed to strike high-value targets
How to See Stealth STEALTH NOT STEALTH DO NOT HAVE BAY DOORS • THE TWO SIDE-BAY DOORS ARE OPEN HERE
SUMMARY Stealth technology referred as “VLO” ie “VERY LOW OBSERVABLE TECHNOLOGY” first true "stealth" aircraft may have been the Horten Ho 229flying wing The goal of stealth technology is to make an airplane invisible to radar RAM reffers to “RADAR ABSORBENT MATERIALS” .RAM Reffers to “RADAR ABSORBENT MATERIALS” . Active cancellation is a theoretical military jamming system Plasma stealth is a proposed process that uses ionized gas (plasma) to reduce the radar cross se ction (RCS) of an aircraft. to degrading the performance of IRST systems is to ensure that the exhaust dissipates as quickly as possible after leaving the aircraft. Over-the-horizon radar is a design concept that increases radar's effective range over conventional radar