subsonic from a supersonic dive. As the air- 
plane slows to subsonic from supersonic speed, 
the airplane will release the leading bow and 
tail waves which formed as the airplane accel- 
erated from subsonic to supersonic speed. The 
release of these shock waves is analogous to 
the case where a surface ship slows to below 
the wave propagation speed and releases the 
bow wave which then travels out ahead of