blackkite said:
Hi Overscan! It might be a duct durning turbofan engine same as P&W JTF17A.
Yes, possibly a duct burner that taps flow out of the high pressure compressor
(to eliminate the choking problem J58 fixed with bypass), and instead send that
to a duct burning arrangement (if you wanted to reduce engine length).
The other possibility is a dry turbojet (no afterburner), but you burn
stoichiometrically (equivalence ratio = 1). The engine there would be short
because there is no afterburner. But the hot section of the motor would
be HOT!
There you need to cool the engine. Because of IHPTET, today they have
materials that can do that, but for late 1960's, they didn't. So if they really
wanted to do this they'd probably have to do something with regenerative
cooling perhaps, for maybe awhile, while the interceptor was speeding to
intercept. But this one is not on the historical charts that I know of.
I don't know if I buy they were trying to really make the engine short, unless
they thought they could do this for significantly less weight than an afterburner.
Larry