Re:Unducted fans?

From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works
Date:         06 Jan 94 01:54:01 PST
References:   1 2 3
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>Just to clear up some terminologies.  UDF is a registered trademark of GE.

I stand corrected.

>Pratt's counterpart ... did not really had a special name

I came upon photos of both testbed aircraft in the February, 1990
Airliners Monthly News.  The MD-80, which had the Pratt engine, is
simply lettered MD-UHB DEMO.

>Correct me if I'm wrong.  Both GE and Pratt practically halted their
>propfan efforts after the cancellation of the 150-seat B7J7 program.

That much rings true.  However ...

>Therefore, I seriously doubt that Delta's order included options for
>a UDF version.  It was proposed to put the UDF on the MD twins, but I
>don't recall an actual offer of MD90/UDF to any customers.

Since the Delta launch order for the MD-90 came in November, 1989,
after the two UDF/UHB/whatever testbeds had been parked at Mojave,
I suspect you may be right.  But I'm certain that Delta did have an
agreement regarding such engines on one of their orders.  If not the
MD-90, it must have been the MD-88s.  I believe it was not an actual
offer by MacDAC, but rather an option to convert some of the orders
or options *if* a propfan offering developed, much as Boeing included
coversion rights on many 737 orders over the past few years, well
before the 737-X became a certainty.

If anyone can come up with a concrete reference to this I'd be quite

>| Seems to me the MD-80 had a GE engine while
>| the 727 had a Pratt, but I wouldn't bet on it.
>I believe Karl is right.

Looks like we both blew this one -- as several others have observed,
and the photographic evidence at least partly confirms, the GE engine
was on the 727 while the Pratt was on the MD-80.

Karl Swartz	|INet		
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