from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of or relating to aerodynamic flow or flight conditions at speeds near the speed of sound.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. just below, or just above the speed of sound
- adj. passing from subsonic to supersonic, or vice versa
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. (of speed) having or caused by speed approximately equal to that of sound in air at sea level
Bullets become unstable when they travel through the "transonic" stage (where the bullet goes from being supersonic to subsonic) the reason for this as best as I understand is due to the change in the way the air flows over the grooves in the bullet that the rifling engraves in its surface.
The 'transonic' stage of a 7mm Weatherby is at about 1400 yards, a 30-06 at about 1200 yards, and my old slowpoke .35 Whelen is at 700 yards.
If bullets become unstable when they travel through the "transonic" stage, then why do 22 long rifle are still flying true even at 600 yards!!!
Such design is very complicated since you fly through all possible flow regimes: From hypersonics down to supersonic, transonic and subsonic.
The LAS can only get on the order of hundreds of feet away from Ares during the transonic region.
The aerodynamics between the tank and tower at transonic.
The term "sound barrier" was coined for when an aircraft attempted to move from transonic to supersonic speed.
Then it had to remain controllable and stable at subsonic, transonic, and supersonic speeds up to Mach 4 by mid-1942, ten years after development had started.
Don't forget to make it stable through the transonic flight without buffetting the rider to pieces.
Although other factors come into play within the transonic ranges, Dynamic pressure is dynamic pressure.