What plane is undetectable by radar?

The F-22 is the plane undetectable by radar, but it is said that the B-1 looks like a flock of birds on radar.

Being undetectable or nearly undetectable on RADAR is known as stealth. There are several stealth aircraft currently in use in the United States armed forces. The F-22 "Raptor" is one of them. . The B-2 "Spirit" Stealth bomber is yet another. The newest in the line of fighter aircraft, the F-35 "Lightning II" is also stealth capable, as well as VTOL (vertical take off and landing) capable in the model for the Marines. The F-117 "Nighthawk" is another stealth aircraft, but has been retired due to obsolescence.

For more information, visit the link below: