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Old June 4th 08, 04:29 PM posted to rec.aviation.piloting
Bertie the Bunyip[_24_]
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Default negative dihedral

Bertie the Bunyip wrote in news:Xns9AB3A5306F330****upropeeh@
208.90.168.18:

Tina wrote in
:

On Jun 4, 4:49 am, HARRY POTTER wrote:
Tina wrote:
I understand how positive dihedral helps dynamic stability in
airplanes, but some big ones, like the Russian An 124 Condor, has

a
pronounced negative dihedral -- the wings have a noticeable
downward slope.

Q1: Do those airplanes need active fly by wire controls to

maintain
stability, or is something else at play that keeps them right side
up?

Q2: Does anyone have a design rationalization for such a
configuration, as opposed to just zero dihedral? I can appreciate
why fighters have it -- they exploit lack of aerodynamic stability
for rapid maneuvers -- but transports that spend their whole life
being straight and level are another issue.

Note: I have not morphed into an Mx clone!

The AN124 does not have negative dihedral. It just looks that way
when it's on the ground because the weight of the engines bends the
wings so they look drooped down. Once it's in the air, the fuselage
bends the wings the other way, so it actually does have dihedral.

--http://onlinelogbook.net


Thanks -- didn't realize it was simply wing droop when they are not
developing lift. That's what happens when you fly in stiff winged
little airplanes, you start overlooking something as obvious as that.


http://www.youtube.com/watch?v=WJscAaKfr7A



Ooops, that was a MSFS one.

Here's an actual aiplane taking off...


http://www.youtube.com/watch?v=BcyRy...eature=related

Which clarly shows the sockpuppet is wrong.


Bertie