"robert arndt" wrote in message
om...
Same here. I live in northern California so I have heard all the stuff
coming from Beale AFB and the Mach 3.0-3.5 range seems to be the
truth; however, the airframe of the SR-71 is stressed for Mach 4.0
flight. Maybe like the Foxbat this was for emergency only with
resulting damage to the engines and a/c. But I see little need for
such speed given the Blackbird's height invunerability.


What height invulnerability? It worked in the 60's but in todays
environment, there are quite a few missiles that could reach out and touch
the SR-71.