Re: Mig 15/17/19
According to everything I've read, the MiG-15 couldn't break Mach 1.
The <a href=http://www.globalsecurity.org/military/world/russia/mig-17.htm?MiG-17 incorporated a lot of improvements over the MiG-15. It probably could go supersonic in a dive like the F-86 but not in level flight. The -17's wings were more swept than the MiG-15s and the engine put out more thrust, so the -17 was a more capable fighter. Thousands of MiG-17s were built, so it was a full production aircraft.
The MiG-19 was a larger twin-engined fighter that could hit roughly Mach 1.3 in level flight.