It must be poor wing design if you have to modify the airfoil with a flow
disrupting rivet head.

My Bellanca doesn't have a wing drop problem and doesn't have any rivet
heads either.

Wonder what the Glass plane builders are doing?
Designing the wing correctly?
--
Cy Galley - Bellanca Champion Club
Newsletter Editor-in-Chief & EAA TC
www.bellanca-championclub.com
Actively supporting Aeroncas every day
Quarterly newsletters on time
Reasonable document reprints

"Roger Halstead" wrote in message
...
On Thu, 15 Jan 2004 17:01:06 GMT, Richard Lamb
wrote:

drake wrote:

Hi all,

Thanks for your replies.

The a/c in question is:
http://www.bharat-rakshak.com/IAF/Im...nt/Deepak.html

The wingdrop problem has been solved (some years back). Just learnt
that all the engineers did was to replace the counter-sunk flat top
rivets on the wing-top (holding the skin to the ribs) were replaced by
protruding pan-head rivets, which apparently energised the flow (made
it more turbulent?). There were rivets all over the wing, but more
towards the wing-root side. This solved the wing drop problem i.e. the
wing drop while stalling was then gentle enough to be handled by
novice pilots. I still am not completely satisfied with the turbulence
explaination... why should a more "energised" flow make the wing drop
less violent?

Sounds like the round head rivets are acting like turbulators.

They have done this in Bonanzas for years.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

If the boundry layer is not attached to the surface, none of the
"energy" in the flow is transfered to the surface.

Basically, tickling the boundry layer like that causes it to reattach
to the surface. That's what they mean by "energizing" the flow.

Make more sense?

Richard (the new improved)Lamb

Hi ya'll!