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Old January 7th 05, 06:23 PM
Mike Rhodes
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On Thu, 6 Jan 2005 23:26:05 -0500, "Happy Dog"
wrote:

"Mike Rhodes"
On Thu, 6 Jan 2005 13:34:48 -0800, "Peter Duniho"

Your assertion that "With full flaps its easy to end up real slow in a
slip
and approach a stall" is just plain nonsense, and certainly has nothing to
do with the *warning* (not prohibition) against slipping while flaps are
extended (even if there were something to your claim about flaps making it
easier to stall).

Pete


Odd, but interesting thread. I haven't heard of tail stall before.


Very uncommon and very serious. Weight and balance (forward C of G) and
icing can cause it. It's just a wing.


I meant in the context of this thread. I'm aware of icing, and that
the tailplane is an airfoil.


But if I've got the basics correct, don't flaps allow the aircraft to
fly at slow airspeeds with a lower angle of attack, including both
wing and tailplane?


Wing.


Meaningless retort. You said "it's just a wing." So you've conquered
the wing? And are looking for other nothings to walk on? Do you have
something against the wing, and other nothings?


So flaps should reduce the likelihood of any
stall, provided enough power is applied to those draggy 40 deg
settings. The wing stalls at a specific angle of attack, and I don't
think the flaps change that characteristic; not that it has been
suggested anywhere.


Flaps change the shape of the wing and allow it to fly at a higher angle of
attack before stall.


No they don't. Are you thinking of slats? This was the point I was
trying to get at in my post. Flaps actually increase the stalling
nature of the wing (though from the safer wing root area) when
referenced to AOA, but not airspeed.

A higher angle of attack before stall allows a higher
coeiffcient of lift.


I have my fluids book in front of me. It has a graph of coefficient
of lift versus angle of attack, and various plots of wings with and
without flaps. In general, the more substantial the flap then the
greater the coefficient of lift (and that coefficient can more than
double; from ~1.5 no-flaps to 3.5 double-slotted). Also, the more
substantial the flap then the _lower_ angle of attack at which the
_wing_ will stall, though only a relatively small (10-25%?) of the
original stall angle.

Stall speed is reduced. Drag is increased. Forward
visibility is improved at slow airspeeds.


Ha! You just proved my point, which you still deny!

Drag increases. Top speed is
reduced (white arc). Trim is affected noticibly. That's all the practical
stuff you need to know. But:


But are you sane?


http://www.aerospaceweb.org/question...cs/q0008.shtml
http://www.aerospaceweb.org/question...cs/q0005.shtml
http://www.av8n.com/how/htm/vdamp.ht...ffect-of-flaps



Actually, read all of this:

http://www.av8n.com/how/


You read it.



I may be wrong, but isn't this one reason why airliners need flaps at
landing? So they don't bounce the tail on touchdown? Or more likely
so the pilot can see the landing area; aside from just reducing
required runway length.


No.


(see my Ha! above)


moo


Are you a cow? with a bullish facade?