One of the factors limiting installed thrust is the ability of the duct to
flow a maximum amount of air mass. I don't see any particular reason why a
different engine (optimized for a different Mach/Altitude) might not be able
to produce more thrust when installed in the same nacelle, flowing the same
mass of air. I'm not an engine person but seems like increasing the
compression ratio, changing the bypass ratio, increasing the turbine temp
and increasing the fuel flow might all increase the thrust level for a given
mass flow rate. Certainly, not every turbofan engine produces the same
thrust when flowing the same mass of air.

Scott Ferrin wrote in message
...
On Wed, 2 Jun 2004 21:23:08 GMT, "breyfogle"
wrote:

The F-101 produces enough thrust for Mach 1.2 to 1.25 and the shock is
stable somewhere in the inlet ducting.

It sounds like you're missing the point. The F101 has enough power to
take the B-1 to Mach 2.2 and had done so prior to the inlet redesign.
Since the inlet redesign it can't go there anymore. Period. More
thrust isn't going to get you a higher top speed. More thrust
(particularly dry thrust) will get you more speed for a given weight
but if the inlets weren't an issue they'd have been fixed from the
start or else a clean B-1B would still be able to hit Mach 2+. It
can't.



The F-119 should produce enough
extra thrust to increase the max Mach significantly.

If you are comparing dry thrust to dry thrust then sure.



Sure, the shock front
moves aft as Mach increases and at some point the shock will reach the
fan
and bad things happen. F-16's & F-18's reach 1.6 (1.8?) Mach with fixed
inlets.

The B-1's speed is limited by the inlets, not the engines. True, the
F119 is optimized for higher speed than the F101 but the inlets will
still make a difference.







"Peter Kemp" wrote in message
news
On Wed, 2 Jun 2004 13:42:25 GMT, "breyfogle"
wrote:

The F119 engines make sufficient thrust to allow high altitude
supersonic
cruise at a Mach somewhat less than Mach 2 while not requiring any
significant change to the current fixed inlets. The tradeoff is a
significant reduction in range.

I thought the requirement for adjustable inlets was to avoid the
supersonic shockwave impinging on the compressor and stalling the
engine. If so, then the thrust of the F-119 isn't oging to help at
all.

Peter Kemp