[net.aviation] Swept-forward wings

jeb@eisx.UUCP (Jim Beckman) (09/24/84)

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Several varieties of two-place sailplanes have swept forward
wings, and it doesn't seem to affect the way they fly.  I have
flown a Blanik fairly often, and didn't notice anything odd.
Most of the two-placers that sweep the wings forward have tandem
seating with wings mounted mid-fuselage or shoulder height.
They want the leading edge to meet the fuselage far enough back
that the back-seat passenger (instructor) can still see over
the edge of the wing.  But putting a straight wing at that
location will put the center of lift too far back, so they sweep
the wing forward.

I believe that swept-back wings contribute something to dynamic
stability around the yaw axis:  if the plane yaws to the right,
the left wing presents more frontal area to the relative wind,
producing more drag and tending to correct the yaw.  This effect
may be fairly slight, I'm not sure.  Isn't the swept wing meant
mostly to deal with high-speed (and supersonic) flight?

Jim Beckman   AT&T-ISL, South Plainfield, NJ   eisx!jeb