KRnetHeads, I have to start this story with two more construction screw ups. First, I laid up some new stub-to-outer wing gap seals a few days ago, using some 3" wide duct tape that I got from the British army (long story there). I erroneously assumed that it would repel epoxy/glass layups just like "Duck" tape, but I now know that I was badly mistaken. The seals took all day Wednesday, and looked marvelous, but when it came time to "pop" them off, it was clear that the seals were now permanently fused to some absolutely awesome military grade tape with an incredible penchant for adhesion. Normally I'd pull the tape back parallel to the surface to minimize the tension on the skin, but the three layers of 9 ounce fiberglass precluded that. Pulling these things off yielded separation of skin from foam, not to mention outright failures of filler (but fortunately only on the primered surfaces, not the painted lower surfaces). That'll take a week to fix. That's not the real story though, just a pre-cursor.
The other thing I did this week was fit a spinner to my plane for the first time. The first flight made it clear to me that this thing was not balanced, even though it's perfectly symmetrical, tracks true, and includes a forward bulkhead. It was OK until I pulled the throttle back to my normal 1600 rpm "base to landing" speed, where it started a disconcerting vibration. I did one landing at a neighboring airport and headed home to remove it. I left the front bulkhead in place though, in anticipation of the carbon fiber spinner that I now plan to make next week, using the spun aluminum one as a mold. I should mention that Troy Petteway installed two new spinners that were both badly out of balance, and then used one as a mold for his carbon fiber version that he's been flying behind for 4-5 years now, with smooth results. If anybody's ever wondered where my mentor is, he lives in Columbia TN. So this afternoon I should have started redoing the body work that will allow me to head towards new stub/outer wing gap seals...but went flying instead....complete with gaping gaps in the wings and a forward spinner bulkhead running interference for the whole airplane. The result was amazing. My first clue was that the climb rate was maybe two thirds what it usually is. For every landing I had to add lots of power to get to the runway. I kept checking the flap light to make sure they weren't down. Wide open throttle yielded only 130 mph max at 2000 feet. That ain't right! On my last landing, I just knew I was so high (to compensate for the drag) that I was going to have to slip it all the way down, but five seconds after getting ready to slip it just after turning final (and deciding not to), I was giving it more power! And during the whole flight there was an annoying vibration that I initially attributed to the engine, but am now pretty sure was some sort of airframe buffeting. Bottom line is that stub-to-outer wing gap seals are vital, even if the gap is only .75", and drag is a REAL factor in KR performance. That tells me that any drag reduction will pay serious benefits in the speed department, which explains Troy Petteway's incredible performance. I knew that already, but I was reminded of it in a serious way today... Mark Langford, Huntsville, Alabama see KR2S project N56ML at http://home.hiwaay.net/~langford email to N56ML "at" hiwaay.net
