---------------------------------------------------------- Lightning-List Digest Archive --- Total Messages Posted Fri 05/18/07: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:38 AM - Re: Gap Seal Experiment Final Day (hopefully) (Brian Whittingham) ________________________________ Message 1 _____________________________________ Time: 06:38:45 AM PST US From: "Brian Whittingham" Subject: Re: Lightning-List: Gap Seal Experiment Final Day (hopefully) Jim, This is for my thesis and the reason why I used two layers of tape is just to make sure that it wouldn't come off in flight. I don't think it would be a big deal if it did, other than I'd have to reattach and for my thesis stuff I'd have to redo some numbers. All stayed on well though. As to why I put the gap seals on top AND bottom, well I looked at where the biggest gaps were in the plane and covered them. The flaps were easy, the bottom of the elevator was too. The ailerons have a gap as well, but the bottom is bigger than the top. The idea is to keep the airflow from the bottom from reaching the top of the wing. That will increase lift, and effectiveness. If I had it to do over though I would put an S-shaped piece of tape to really tightly seal the ailerons off from air going through the gap. We did learn a few lessons with the whole thing about how we would do it different. I think that we'll see an increase in lift for sure. I believe we saw 1-2 knot increase in stall speed. (I think the numbers were 43 kts before 45 after) Not a big deal, but it was one of the things I hypothesized would happen. Haven't had a chance to play with the numbers yet. I traveled to Arkansas last night and will stay another night here to visit with family and head on to Texas. One really interesting thing that we found was that we had a little right roll in the plane before the mod. Just never got around to fixing that yet. When we put on the gap seals it was much more noticible in the stick force to hold the plane in level flight. The plane wanted to roll to the right more. To me that's a quick and easy determination of a couple of things. We got increased aileron authority, and an increase in overall lift. I'll let you all know the final results though. Brian W. Brian: What youa re doing is pretty exciting and thanks for the efforts. Can you tell me why the tape is applied to the top and bottom of the aileron gaps? I am curious why not just the bottom? Jim! _________________________________________________________________ PC Magazines 2007 editors choice for best Web mailaward-winning Windows Live Hotmail. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message lightning-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Lightning-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/lightning-list Browse Digests http://www.matronics.com/digest/lightning-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.