The F-117 is used as a strike aircraft, delivering ground ordnance on targets. The F-117 is a stealth aircraft which means it is nearly invisible to standard radar. This allows it to penetrate radar and attack targets in the dark before it can be detected and intercepted.
A radar system sends out a wave. When part of this wave hits something, it bounces back to the radar receiver, the radar can then work out the size, location, and also the velocity of the object.
A stealth plane is specially made to scatter radar waves across its angular surface. The radar might not be able to detect it, or estimate that the object is far smaller than any military vehicle and therefore not sound any kind of alarm.
A British Rolls-Royce Merlin engine which is a liquid-cooled V-12 piston aero engine of 27-litres.
Currently, the B2 Spirit and the F22 Raptor.
The F117 Nighthawk has been retired, as has the 'reduced RCS' SR-71 Blackbird.
The F35 isn't scheduled to be delivered until 2016.
First flight 1981 to last in 2008 a total of 64 were built. 59 were designated fighters with 5 demostrators. With one confirmed kill.