The U.S. Air Force has revealed how “stealthy” the F-22 is. It’s RCS (Radar Cross Section) is the equivalent, for a radar, to a metal marble. The less stealthy (and much cheaper) F-35, is equal to a metal golf ball.09-12-2005 - Washington -- The F-35 stealthiness is a bit better than the B-2 bomber, which, in turn, was twice as good as that on the even older F-117. Much older aircraft, like the B-52, have a huge RCS, which makes them very easy to spot on radar. But with a smaller RCS, it's more likely that the aircraft won't be detected at all.
The air force revealed this information, which is usually kept secret, because it wants to make the case that it makes more sense to cut production of the F-35 (which cost $30-50 million each), so that more F-22s (that cost over $100 million each) can be bought.
The range of the diameter for glassy marbles is from 12mm to 42mm, and according to the formula, the range of cross section area for glassy marbles could be from 0.0001m2 to 0.0014m2. As for the marbles with the most common size (14.4mm and 16mm in diameter), their cross section area shall be 0.00016m2 and 0.0002m2.
The standard golf ball today is 1.68 inch (4.2672 cm) in diameter. According to formula, its cross section area shall be around 0.00143m2, which is about 7~9 times bigger than the minimal frontal RCS of F/A-22, but 1/35~1/70 of the frontal RCS of the western fighters such as EF-2000, Rafale and the F/A-18E/F.