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COMBAT AIRCRAFT SURVIVABILITY. PRESENTED BY: MOHD AFNAN BIN MOHD SANI 0432107 MUHAMMAD FAIRUZI BIN MOHD YUSOF 0432803 MOHD ZAIME BIN MISRI 0435635. Video of an aircraft (MIG-21) that was attacked by missile .
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COMBAT AIRCRAFT SURVIVABILITY PRESENTED BY: MOHD AFNAN BIN MOHD SANI 0432107 MUHAMMAD FAIRUZI BIN MOHD YUSOF 0432803 MOHD ZAIME BIN MISRI 0435635
Aircraft combat survivability (ACS) is defined as the capability of an aircraft to avoid or withstand a man-made hostile environment including both man-made and naturally occurring environments, such as lightning strikes, mid-air collisions, and crashes It can be measured by the probability the aircraft survives an encounter (combat) with the environment
The traditional discipline known as system safety attempts to minimize those conditions known as hazards that can lead to a mishap in environments that are not made hostile by man Thus, together, the system safety and survivability disciplines attempt to maintain safe operation and maximize the survival of aircraft in all environments in both peacetime and wartime.
The survivability of an aircraft is related to the aircraft's killability, or susceptibility and vulnerability, by the equation PS = 1 - PK = 1 - PHPK|H Survivability = 1 – Killability = 1 - Susceptibility • Vulnerability Thus, an aircraft's combat survivability is enhanced when it's killability is reduced. The killability of an aircraft is reduced when the susceptibility and the vulnerability of the aircraft are reduced
What is aircraft susceptibility? Susceptibility isthe inability of an aircraft to avoid Guns Missiles Air interceptors Radars 6
The important susceptibility measures is probability of detection by the enemy Its strongly dependant upon the size of the signature of the aircraft Aircraft signature radar signature visual signature infrared signature aural signature 7
Radar signature When the signal passes over the aircraft A portion of the incident power absorbed as heat Another portion pass completely through parts of the aircraft The remainder is radiated or scattered in many different directions 8
IR signature General sources of IR signature are radiation emitted by airframe and propulsion system exhaust gas and plume from the engine typical major IR sources 11
Visual signature The visual detect ability of an aircraft is dependent the difference between the background and the aircraft. Aircraft detection occur when the aircraft luminance is too low compared with its background Camouflage of fighter aircraft 14
Aural signature Aircraft are often heard before seen by ground observer Primarily as a result of engine or rotor blade noise Example Low-flying helicopters sound can heard as 30s before they become visible because of rotor blade noise 15
Design for Low Susceptibility 5 susceptibility reduction concepts Signature reduction Threat warning Radar deception Expendables Weapons and tactics, flight performance and crew training 16
Reduction of radar signature Reflection of the radar signal away from the receiving antenna a. shaping and orienting conducting surface b. aligning all edges in few direction Absorption radar signal using special Radar Absorbent Materials RAM) or Radar Absorbent Structures called RAS 17
Reduction of infrared signature (IR) Reduce the temperature of the hot parts Reduce the surface emissivity of the hot parts Reduce the temperature of the exhaust Reduce or mask the observable surface radiating area For reflecting surfaces reduce the surface reflectivity 18
Threat warning The system has been build to warn the pilot if they are being targeted by enemy Example Radar Warning Receivers (RWR) Missile Approach and Warning System (MWS) 20
Radar deception Deception system consists of those electronic techniques that present false target information to the radar General approaches for deception To provide incorrect target bearing, range, or velocity information to the radar 21
Expendables Material or devices to be ejected from an aircraft for the purpose of denying or deceiving threat tracking system for limited period Example Chaff (confuse radar) Aerosols Flares (IR decoy) 22
Weapons and tactics, flight performance and crew training and proficiency This last concept is somewhat of a catch all concept. It combines all of the operational aspects 24
Vulnerability Aircraft vulnerability refers to the inability of the aircraft to withstand the damage caused by the man made hostile environment, to its liability to serious damage or destruction when hit by enemy fire. Aircraft that are more vulnerable are softer, where as those are less vulnerable are harder.
Type of aircraft kill • Attrition kill category
Mission abort kill category • prevents an aircraft from completing its designated mission and minimum flying qualities remains after the hit • Mission denial kill category • aircraft is hit and the pilot unable to control the aircraft, and aborts the mission because of the aircraft damage. (Mission objectives does not achieved) • Landing kill category • Carrier base aircraft are able to return to the carrier but cannot land because of the damage to the tail hook. • Forced landing category • It is helicopter kill category in which damage to the helicopter causes the pilot to land (powered or unpowered) because of receiving the indication of component damage.
Critical components kill modes. • Component dysfunction, damage, failure or kill • The inability of a component to provide the function it was designed • Components kill modes. • failure modes and damage modes • System kill modes • Loss-of-function kill modes • Loss of essential functions • Cascading-damage kill modes. • When a damage component that can kill other critical component
Vulnerability reduction concepts • Component redundancy • total redundancy and partially redundancy • dual electrical generators where a single generator only powers some of the aircraft systems • dual power control hydraulic subsystems • Component location • positioning critical components that can reduce the probability of lethal damage
Passive damage suppression • providing redundant load path in critical structural elements such as multispar wings • Active damage suppression • fire detection and extinguishing system that uses a detector to sense an ignition source of high temperature area • Component shielding • Providing armor material to the critical components as a shields • Component elimination or replacement • replacing a fuel-feed boost pump with a fuel-feed suction device
Some Survivability Enhancement • Speed and altitude • Maneuverability/agility • Chaff and flares • Fighter escort • Self-repairing flight controls • No fuel adjacent to air inlets • Self defense missiles and guns • Good target acquisition capability • Night-time capability • Crew situational awareness & Tactics • Threat warning system • More than one engine – separated • Low signatures • Antiradiation weapons • Nonflammable hydraulic fluid
CONCLUSION The survivability community must apply lessons learned from combat and tests to improve future system design, performance capability, and survivability against anticipated lethal and nonlethal threats. So, to increase the survivability of combat aircraft we have to decrease the susceptibility and vulnerability of the aircraft.