Why a Swept-Wing?
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January 11th 04, 06:10 PM
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"Air Force Jayhawk" wrote in message
On 11 Jan 2004 05:39:04 -0800,
Pardon my ignorance on all matters concerning modern aviation but just
why the hell would you want to sweep a wing forward?
Doesn't that make any aircraft unstable? If so, why would any pilot
feel safe in it?
Has anyone ever made one work?
An aircraft is only unstable if the aerodynamic center is forward of
the center of gravity. If the wing root is sufficiently aft and the
AC stays aft of the CG, stability remains.
Why? Well it was tried with the X-29 but I never have read why no one
has pursued it since. The advantage was supposed to be that the
boundary layer (the thick air right next to the surface caused by
friction and very annoying) builds up as the air moves aftward along
the wing. With a FSW, the thickest part of the BL is at the root
rather than near the control surfaces, enhancing control while at high
angles of attack. There are other advantages but it's been a while so
I can't recall them off the top of my head.
I knew the USAF pilot on the X-29 project...he said it flew fine and
had no issues with it.
USAF got shafted on the X-29 and would have never built the second airframe,
had they known about the flutter problem. NASA falsified the flight test
reports such that they indicated the wing flutter sensor was within limits,
when in fact, the data went full scale and drew a straight line.
What would a pilot know about a vehicle? You've been there Rosco, how could
they possibly know?