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In SR-71 Revealed, a book written by an SR-71 pilot and squadron commander, the author addressed this and to the best of his knowledge, the USAF and Lockheed bo
by tastygreenapple 7y ago
In SR-71 Revealed, a book written by an SR-71 pilot and squadron commander, the author addressed this and to the best of his knowledge, the USAF and Lockheed both don't know the true top speed of the SR-71.
(Doing this from memory so I may get something wrong here), the SR-71 usually cruised at mach 3.2, it could accelerate to mach 3.3 when fired upon, and could go to mach 3.4 if the pilot felt it was critical to preserve the crew/airframe however the plane needed to return to base after getting out of harms way and needed to be inspected before returning to the flight line. A lockheed test pilot apparently got the SR-71 to mach 3.5 (or maybe Mach 3.6?) but said it started to get scary. If this is accurate, it's probably the case that no one knows what fails first on the SR-71.
- redis_mlc 7y agoThe SR-71 had a moving engine inlet spike, so that would be an operating limit based on temperature and speed. Fun fact: the SR-71 flew its entire mission in radio silence, including multiple aerial refuelings, to avoid pesky Russian trawlers, etc. tracking it. Generally aluminum is good to Mach 2.2, then you go to steel or titanium for either leading edges or the entire fuselage. Which makes the F-5 all that more impressive, as its fuselage was designed for Mach 2.0, near the limit of aluminum, even theough the engines limited it to Mach 1.3 to Mach 1.6. (The F-5 was so small that it was optically stealthy - adversaries couldn't see it outside 5 miles.) Titanium was used as a last resort in the F14 to reduce weight in the central fuselage box, which meant building the world's largest titanium casting plant at the time. Your tax dollars at work.