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Stealth characteristics

  1. May 21, 2005 #1
    What characteristics must a airplane have in order not to be visible on enemy's radar screen?
  2. jcsd
  3. May 21, 2005 #2


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    - Geometry that deflects radar signals away from the originating radar instead of back to it.
    - Radar absorbing materials to lessen the radar image that does get returned.
    - Minimized heat signiture via dispusion of jet engine exhaust.
    - The F22's radar is supposed to have technology that even though it is on and picking up targets, the targets can not pick up the F22's radar. In current realms, once a radar is put in use, everyone else knew where you were.
  4. May 31, 2005 #3
    Those characteristics are all correct. The shape may be polygon-like like the f-117 or more smooth like the b-2 and f-22. It seems that acute angles favor stealth characteristics. If you look on the f-117 you wont find many oblique angles on the craft and especially not any right angles. Also notice that there are no protruding edges like external missiles. As for the radar systems, I believe the f-22 uses something I like to call passive radar. This means it picks up the enemy aircraft's radar by simply detecting the waves. It does not put out its own to sense aircraft. When a missile is fired however, I believe the f-22 uploads the guidance data to the missile for a short while on very low bandwith signals. Once the missile is far enough away from the f-22 it turns on its own radar and tracks the enemy aircraft with that. This way the radar spike as detected by the enemy is that of the missile which is about to become non-existent and not that of the f-22. You also need to coat the craft in RAM. I really dont know exactly how the chemicals react with radar, but i'd assume ram acts like a 2 sided mirror. Once the light beam enters through a glass like surface, it reflects off the aircraft, but this time it rebounds off the backside of the incident surface which is either reflective or it might have a very high index of refraction. If this is true the light becomes trapped in the ram and will eventually dim out, just like a beam going through a hundred feet of water. It becomes very weak after traveling some distance in the ram. I guess in theory if you hit a stealth with some really strong radar the RAM would get really hot and you could cook eggs on it.
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