The SR-71 ran on two J58 turbojet engines and cruised at Mach 3.2.
What I want to know is, what is the actual exhaust velocity (relative to the airplane itself) of the jet exhaust at those conditions?
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Sign up to join this communityThe SR-71 ran on two J58 turbojet engines and cruised at Mach 3.2.
What I want to know is, what is the actual exhaust velocity (relative to the airplane itself) of the jet exhaust at those conditions?
It's not a cut and dried single figure but this SR-71 PROPULSION SYSTEM - P&W J58 ENGINE (JT11D-20) seems to have enough information to allow you to arrive at a reasonable figure with 'some work'. If I had to choose one information source to get a feel for the answer this would be on the short short list (so far :-) ). Unlike most other sources, the result will be at least somewhat meaningful, if not overly accurate.
It also seems to make it 'clear enough' that if someone gives you a simple unqualified numerical answer it will be meaningless, or wrong, or both :-). It's a 44 page PDF slideshow - but has enough detail to show how different the J58 is to what you may expect.
He also supplies these references which will almost certainly be interesting, and possibly also useful.
More M&PW answers:
and here
Somewhere in here probably :-).
Related;
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