> <> I understand why the engines have to be in closed nacelles tucked in
> tightly to the body and wing, but why not on TOP of the wing, where debris
> from an exploding tire wouldn't be a problem?
This is an issue with more than just the Concorde. The Mig 29 has
similar problems with the forward landing gear kicking debris right into
the intakes of the engines. THis is resolved with that bird with the
help of a retractable intake screen and ducts that feed air from above
the wing if needed. Modern SST designs do put the engines above the wing
to deflect sound upward, rather than down.
Reasons for putting them below the wing:
a) so ground crews can work on the engines on the ground, without
needing to tow around platforms to access engines above the wing (which
could also damage the rear edge of the wing if not treated right), or
being at risk of falling off the wing in icy or wet weather (back
injuries being a seriously prevalent disabling injury from falling off
b) so aircraft taking off can take of in less distance and can climb at
steeper angles of attack. Putting engines above the wing reduces
pressure of air entering the engines, and thus thrust put out, while
putting them below increases air pressure entering engines...
This archive was generated by hypermail 2b29 : Mon Oct 02 2000 - 17:35:19 MDT