Bobby, My pilot is a high time (18,000 hr.) pilot, test pilot for the Raspet Flight Research Lab at Mississippi State University with experience in hundreds of aircraft. He has experienced this before in the "Marvel" research aircraft where the wing area was increased without proportionally increasing the horizonatal stabilizer area. This occurred at that time. The horizontal stabilizer area was increased and the problem was solved. It became stable through full stall. You might like to communicate with some other KR-2 builders who did build a true airfoil horizontal stabilizer (not flat on top) and seek their opinion. My problem could be caused by the changes I make in the fuselage. My canopy sits 3-4 inches higher than the standard, it is very sleek with very little drag. I used a dragonfly canopy and built the turtle deck to fit. (I get 135 mph indicated at 2800 rpm). After I put wheel pants on it and some fairings elsewhere I hope I will get a little higher MPH. Thanks for your interest. I will keep you posted as to the results of increasing the area of my horizontal stab. Bill Page boliverp...@bellsouth.net
----- Original Message ----- From: <bo...@hatconversions.com> To: "KRnet" <kr...@mylist.net> Sent: Thursday, April 13, 2006 7:19 PM Subject: Re: KR> Horizontal stab stall > Bill, > I spent lots of time in my Mustang II with guys that were used to > flying General Aviation aircraft. Every one wanted to fly it. In all > the time I had it (800+hours) I can't remember anyone that was > successful at a stall sequence the first time. With out fail, > everyone over controlled it going into the stall, and more critical, > coming out. We either ended up in an accelerated stall or a couple of > times it actually snapped upside down. > Don't know what your qualifications are, but is there a chance it > would be worth letting a high time experimental pilot test fly it, or > maybe get one of the active KR2 guys to come fly it for you? > > The reason I am asking these questions is I have an original fuselage > with a set of Diehl wings almost ready to fly. Keep us updated. > Bobby > > > > > > > Bill, >> KR-netters >> >> After consulting with the Aerospace Department at Mississippi State >> University concerning the pitching up of my KR-2 upon stall approach, a >> probable cause has been reached. The Horizontal Stabilizer is stalling >> prior to the wing stall. This may be caused by the longer wing by Dan >> Deihl. This creates a very dangerous condition. There are three ways to >> prevent this condition. (1) Increase the stabilizer area by increasing by >> several inches the length of the stab. The standard flat stabilizer is >> only about 50% as efficient as a stabilizer with a true airfoil which >> leads to the 2nd method of prevention. (2) Change the stab airfoil to a >> true airfoil which will increase the efficiency of the stab. And (3), >> Don't stall the aircraft, keep the airspeed well above stall. >> It has been noticed that some KR-2 builders constructed a true airfoil >> rather than the flat stab shown in the plans. Maybe it should be noted to >> other KR builders to do the same. >> You guys who have true airfoil stabs, where did you get your plans, >> technical info., etc. I would like to change my stab to a true airfoil. >> >> Maybe if I put Armorall on my horizontal stabilizer my problem will be >> solved. >> >> I'm still finding dingle berrys after that close call. >> >> Bill Page >> boliverp...@bellsouth.net >> _______________________________________ >> Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp >> to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net >> please see other KRnet info at http://www.krnet.org/info.html >> > > > _______________________________________ > Search the KRnet Archives at http://www.maddyhome.com/krsrch/index.jsp > to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net > please see other KRnet info at http://www.krnet.org/info.html >
