 Highly-stealthy aircraft like the F-117 Nighthawk are aerodynamically unstable in all three aircraft principal axes and require constant flight corrections from a fly-by-wire (FBW) flight system to maintain controlled flight.It is shaped to deflect radar signals and is approximately the size of an F-15 Eagle.The single-seat Nighthawk is powered by two non-afterburning General Electric F404 turbofan engines.