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View Full Version : Anyone use winglets on built-up wings?

Pierre Audette
Jul 26, 2002, 10:23 AM
Just wondering if anyone uses them and find them useful in improving a sailplane wing efficiency. Looking at full size sailplanes, they tend to use narrow and tall winglets at the trailing edge of the tips.
Bob Reynolds
Jul 26, 2002, 03:15 PM
Yes, on my electric ducted fan, "Probe". Don't know if they help, but they sure look cool.:)
Doc Data
Jul 26, 2002, 03:33 PM
A club member's Casiopea...
http://www.mustangone.com/thermalriders/FredCasiopea3.jpg
http://www.mustangone.com/thermalriders/FredCasiopea2.jpg
... and I know he is very pleased with the plane. Not sure who makes/made it.

dd.
Pierre Audette
Jul 29, 2002, 10:39 AM
Well I did a simple mod on the Skimmer 400, sliced off 1/4" off the tips to get a straight edge, cut some 1/16" ply into winglets, and used spackle to make some fillets. I tried it out in some fairly strong wings, so I can't say for sure if it's made any improvements on the glide, but it sure looks like it means business.
Tony Oliver
Jul 30, 2002, 06:41 PM
Yes, I've used them - I put details on the Forum a while ago, but the basics were:-

130 inch span wing on contest thermal soarer, no real clear change in performance, but they looked great (to me!). They were very vulnerable to damage.
Finally took one off the model and flew it - no trim changes needed - it didn't turn into the missing winglet so there was no obvious increase in lift from the wing which still had one. End result was that they had no obvious useful effect.

I've tried Hoerner tips, downswept, upswept, tipfins.

Downswept had the most useful effect, keeping the wing out of the mud on wet day landings.

Tony
Sabrejock
Jul 30, 2002, 07:36 PM
Winglets which point upwards on full scale planes are efficient mostly at selling airplanes. Buyers want them so builders put them on. Downward pointing winglets would be quite efficiency enhancing, but builders are reluctant to use them because ramp rats would always be knocking them off! And it would severely limit the cross-wind certification.

They seem to be getting smaller, though, and I suspect will eventually disappear. Tex.