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From: David Lednicer <dave@amiwest.com>
Subject: Valsan 727 modifications
Date: 20 Mar 94 22:30:06 PST

	I have been asked what the Valsan reengining program is, so I
will describe it here.

	The Valsan program was intended to make 727-200s compliant with the
Stage 3 noise rules.  The outer (#1 and #3) JT8D-9, -11, -15 or -17s are
replaced with JT8D-217s, which have a higher bypass ratio and are
quieter.  The -217s are the engine found on the MD-82.  The center (#2)
engine, being buried in the tailcone, could not be easily replaced, so
instead it looses its thrust reverser and gets an internal (bypass/core)
mixer, to lower its noise signature.  The first modified aircraft, for
Sterling Airways of Denmark, re-entered service in October 1988.
Aircraft modified have included some Continental aircraft and high
gross-weight Federal Express -200s (late model aircraft).  After
certifying the modified -200, Valsan also certified a similarly modified
727-100.  I believe that the first aircraft was a corporate aircraft
owned by the Limited.  Stories I heard indicate that the reengined -100
is a real hotrod.  Since this time, Valsan has also certified and put
into service winglets on the -100 and -200.  These are intended to cut
cruise fuel burn.  A 5% improvement is claimed.

	The RR Tay reengining program is being conducted by Dee Howard
for United Parcel Service.  In this case, all three engines are replaced
by Tay 651-54s.  This is a more extensive mod, as the #2 engine air duct
has to be completely replaced.  The aircraft also gets a glass cockpit at
the same time.  Dee Howard is under contract to modify 80 aircraft for
UPS.  Several are now in service.

	The other 727 program is a Federal Express hushkit.  This kit
adds internal mixers to all three engines of a -100 or -200.  Fedex has
installed them on most of their older 727s and Trump/USAir shuttle and
Delta also have sprung for this kit.  My impression is that this is a
cheap modification that involves some gross weight trade-offs for Stage 3
compliance.

	Both the Valsan and Dee Howard kits up the aircraft's available
thrust.  Some Valsan engineers told me about taking off in a modified
727-100 with the spoilers inadverantly actuated.  They claimed that the
rate of climb was still better than with the old engines!  In fact, they
were talking at one point about removing the #2 engine altogether and
turning the 727 into a twin!



-------------------------------------------------------------------
David Lednicer             | "Applied Computational Fluid Dynamics"
Analytical Methods, Inc.   |   email:   dave@amiwest.com
2133 152nd Ave NE          |   tel:     (206) 643-9090
Redmond, WA  98052         |   fax:     (206) 746-1299


 
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