Washout?

Rich S. wrote:
"cavelamb himself" wrote in message
...

Rich S. wrote:

Even with washout, the Emeraude (elliptical planform - 23012 airfoil)
will stall fairly abruptly. Like, at 50 you're flying - at 49 you're not.

Rich S.

That's a function of the wing planform - not the airfoil.


That's what I said.

The info on airfoil was for comparison with the "Hershey bar" RV wing - the
same airfoil - different planform.

Rich S.



Just checkin'

Some guys like to think it's the airfoil.

Richard

"cavelamb himself" wrote in message
...

Just checkin'

Some guys like to think it's the airfoil.

Gotcha. It's a bit ironic. You go to all the trouble to build a neat looking
elliptical wing (I love a Spit and a Jug for that reason) and you get a
sharper stall than a plain jane rectangular wing. 'Taint fair!

Rich S.

Rich S. wrote:
"cavelamb himself" wrote in message
...

Just checkin'

Some guys like to think it's the airfoil.


Gotcha. It's a bit ironic. You go to all the trouble to build a neat looking
elliptical wing (I love a Spit and a Jug for that reason) and you get a
sharper stall than a plain jane rectangular wing. 'Taint fair!

Rich S.




Yeah, but you reduce induced drag and bending moment,
so I guess it's a wash...

out


Richard

On Tue, 25 Mar 2008 02:00:20 -0600, cavelamb himself
wrote:

Rich S. wrote:
"cavelamb himself" wrote in message
...

Just checkin'

Some guys like to think it's the airfoil.


Gotcha. It's a bit ironic. You go to all the trouble to build a neat looking
elliptical wing (I love a Spit and a Jug for that reason) and you get a
sharper stall than a plain jane rectangular wing. 'Taint fair!

Rich S.




Yeah, but you reduce induced drag and bending moment,
so I guess it's a wash...

out


Richard

I'll still go with what I wrote.

stick some vortex generators out in the last yard to the tips and see
how that goes at keeping the flow attached Mr Shankland.

dang I'll need to build my turbulent with the slots.
Stealth Pilot

Thanks for all the advice and discussion. Looks like stall strips
could be the way to go. I think I'll experiment with the VGs too.
BTW, the wing is rectangular.


Or put a "triangle" shaped addition on the leading edge of the wing's root,
to trip that portion into stall, first.

That's all anyone is after with washout. Keep the outer portion flying,
while the root is stalling.

If it were me, I would probably do a bit of both! g

Advantages of keeping the wing with no washout is that the whole wing will
be lifting at cruise, instead of throwing away part of the outer wing's lift
with added washout.

big john and morgans have it with the triangular strips.

you just tape them on and keep shortening them until you have the
stall chracteristics you need. then you replace the temporaries with
permanent ones.
make both sides identical.
work out where the 3 degree angle of attack neutral point is on the
leading edge and stick them there.

wrote:

Thanks for all the advice and discussion. Looks like stall strips
could be the way to go. I think I'll experiment with the VGs too.
BTW, the wing is rectangular.

See....
http://selair.selkirk.bc.ca/aerodyna...l_Pattern.html

Since the AOA is reduced by the up-wash we must predict that a
rectangular wing will have a greater effective angle of attack at the
root, and therefore will stall first at the root.

YMMV.

- Barnyard BOb -

Barnyard BOb wrote:

wrote:


Thanks for all the advice and discussion. Looks like stall strips
could be the way to go. I think I'll experiment with the VGs too.
BTW, the wing is rectangular.


See....
http://selair.selkirk.bc.ca/aerodyna...l_Pattern.html

Since the AOA is reduced by the up-wash we must predict that a
rectangular wing will have a greater effective angle of attack at the
root, and therefore will stall first at the root.

YMMV.

- Barnyard BOb -



Which brings us all back to the question What Is It???
Rectangular wing or soemthing else?

Richard

--
(remove the X to email)
cave page at:
http://www.home.earthlink.net/~cavelamb/index.htm#top


It's never too late to be
the person you might have been.
George Elliot

"cavelamb himself" wrote

Which brings us all back to the question What Is It???
Rectangular wing or soemthing else?

I recall being told rectangular, but only after all of the stall strip
advice began flowing.

As Barnyard said, probably no need to do anything with rectangular, but I
would thing if it was found to be needed afterwards, adding a stall strip
would be easy enough.
--
Jim in NC

"cavelamb himself" wrote in message
...
Rich S. wrote:
"cavelamb himself" wrote in message
...

Just checkin'

Some guys like to think it's the airfoil.


Gotcha. It's a bit ironic. You go to all the trouble to build a neat
looking elliptical wing (I love a Spit and a Jug for that reason) and you
get a sharper stall than a plain jane rectangular wing. 'Taint fair!

Rich S.


Yeah, but you reduce induced drag and bending moment,
so I guess it's a wash...

out

Just like putting some washout into a rectangular wing.


;-) ;-)


--
Geoff
The Sea Hawk at Wow Way d0t Com
remove spaces and make the obvious substitutions to reply by mail
When immigration is outlawed, only outlaws will immigrate.

"Stealth Pilot" wrote in message
...

stick some vortex generators out in the last yard to the tips and see
how that goes at keeping the flow attached Mr Shankland.

dang I'll need to build my turbulent with the slots.

I wouldn't change a thing, actually. The abrupt stall isn't a problem at
all - if you know it's coming. After the stall, you can hold the stick in
your lap and, if you are quick on the rudder pedals, you can maintain a heck
of a rate of descent in a level attitude. Let it go a bit too far though and
she'll be in a spin right now. Normal recovery technique stops the spin
within a turn.

Rich S.