There is a constant change in the type of aircrafts, especially the fighter planes.

The biggest enemy of a fighter plane is radar. Whenever the plane crosses the borders of a foreign coumtry, it is immediately trapped and followed by radar. The powerful microwaves produced by radar are bombards on the body of the aircraft and is transmitted back and captured by radar. This produces an image of the plane on the radar.

In order to prevent the radar attacks, some scientists of Mishigan Laboratoties, America have developed " Steelth Cruice Planes". The aircraft body is manufactured as such that it prevents the microwaves from transmitting back. They are absorbed on the oute suface of the plane. The wings of such planes are coloured with excessive content of ferrite material due to which all the microwabes  produced by radar and electromagnetuc waves are absorbed and the image of the plane is not produced on the radar.

Such planes are not yet available with any country but they are manufactured and practised at theSawyer Airforce Station, U.S. The research for invisible aircrafts is done by Advancement Of Microwave And Electronics And Engineering Department.