Re: B747 technical questions

Date:         03 Aug 97 02:50:16 
From:         Steve Lacker <CAN_SPAM@arlut.utexas.eedu>
Organization: applied research laboratories
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Karl Swartz wrote:
> >The Dash 80 also carried a 5th engine to support the 727 program.
> >The JT8 was mounted just in front of the aft starbord cabin door ...
> Ok, that's how the JT8D was flight tested.

Errrr.. Was it?!? I thought that the engine flown in that location was
just a JT3D (or maybe even a J-57), mounted there by Boeing to
investigate the effects of applying thrust at that location on the
airframe. I could easily be wrong, but it seems to me that the
ridiculous tailpipe (ever seen a picture of it? Its good for a laugh or
two!) would have completely invalidated any realistic in-flight testing
of a new powerplant like the JT8D. One couldn't even argue that it
simulated the S-duct of a 727 since that is on the inlet side of things.

> The JT9D was flight tested
> on a B-52 and the RB.211 was flight tested on the port pylon of a
> VC-10.  How was the CF6 flight tested?  Perhaps on a C-5A, from whose
> TF-39 engines the CF6 was developed?  On what, then, were the TF-39
> engines flight tested?

Good questions which I'd never thought to ask... since the TF-39 was a
military development, I could envision it having been flown on a B-52
also, but I'd like to hear a definitive answer.

Stephen Lacker
Applied Research Laboratories, The University of Texas at Austin
PO Box 8029, Austin TX 78713-8029