The F-119 engined F-22 has fixed inlets and is not especially fast.

What makes you think fixed inlets make a difference?


The engine, therefore, does _not_ have to be made of the *very*
expensive highest-temperature alloys.


The F119 is made of MUCH better alloys than the J93. I think the
temperature problem is handled by the fact that the J93 compresses the
air much less than an F119. So does the J58 and the engine the Mig-25
uses.


My question is, how long would
the F-119 last in a mach3 aircraft like the B-70?