---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Tue 02/24/09: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:56 AM - Re: Re: weight question (pj.ladd) 2. 06:34 AM - Re: firestar first flight (N111KX (Kip)) 3. 08:03 AM - Re: Re: xtra wingtip mods (John Hauck) 4. 08:08 AM - Re: Re: weight question (John Hauck) 5. 09:12 AM - Re: weight question (JetPilot) 6. 10:25 AM - FireFly Stall Pre-Buffet (Jack B. Hart) 7. 03:21 PM - Re: Re: weight question (pj.ladd) 8. 03:49 PM - Re: Re: weight question (John Hauck) 9. 07:33 PM - Re: xtra wingtip mods (icrashrc) 10. 07:52 PM - Re: Re: xtra wingtip mods (John Hauck) ________________________________ Message 1 _____________________________________ Time: 04:56:02 AM PST US From: "pj.ladd" Subject: Re: Kolb-List: Re: weight question How do you determine "natural buffet speed?>> Hi John, it is just a note of the speed at which the plane shakes to tell you to drop the nose a tad or you wil stall. It is just one of the boxes that needs ticking for the annual check. No idea what use is made of the information. I suppose if you had a plane which gave no warning of an incipient stall it would be worth knowing. Pat ________________________________ Message 2 _____________________________________ Time: 06:34:19 AM PST US Subject: Kolb-List: Re: firestar first flight From: "N111KX (Kip)" Great job, John! Thanks for bringing another Kolb into the world... [Laughing] Kip -------- Kip Firestar II, N111KX Waiex, N111YX Quickie 1, N111QX Atlanta Read this topic online here: http://forums.matronics.com/viewtopic.php?p=231794#231794 ________________________________ Message 3 _____________________________________ Time: 08:03:11 AM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: xtra wingtip mods > Aileron mass balances are tested and built. > > http://www.ill-eagleaviation.com/AileronMassBalance.htm > > I also started the page on the wing center section(gap fill). > > http://www.ill-eagleaviation.com/WingCenterSection.htm > > Scott Morning Scott: Looks good. When I built my mkIII in 1991, I knew I needed aileron counter balance weights. Both my Ultrastar and Firestar suffered from aileron flutter. I could not convince Kolb Aircraft I had a flutter problem, so I designed and built my own. Wish I had a photo of them. They were pretty. Built similar to your design, I used 1/8" aluminum plate instead of 4130 streamlined tubing. My weight was tubular with a turned round nose and tapered tail. I attached them to the inboard end of the aileron. Early on, during testing, I experienced severe aileron flutter them installed. Happened to be at the local airport, landed, and promptly removed them. Flew to Lakeland, Homer's in PA, and OSH, in 1993, always sitting on the edge of my seat trying to keep the mkIII close to 80 mph. A couple over and she would start to flutter. Had a hell of a time trying to fly off a Cessna 210, at OSH, doing the photo shoot. He was trying to slow down to 80 and I had to fly faster than 80 to stay up with him. Think it was Lakeland 1994, Dick Rahill had been out flying the Firestar, got caught is a typical Lakeland wind storm, was trying to beat feet back to the UL strip, and got into very severe aileron flutter. Now Kolb Aircraft believed their airplanes were susceptible to aileron flutter. In a matter of days I had a copy of the new aileron counter balance weights designed and built for the FS. Their factory mkIII never fluttered and they were not convinced it needed them. I flew with the FS counter balance weights on mty 17,400 mile trip to Alaska and around the country in 1994. They were a blessing. My mkIII has never had a hint of aileron flutter since I installed them. Made my flying 100% more comfortable. Soon after they designed and built aileron counter balance weights for the mkIII. I really like the center section. Wish I had one similar. Being an amateur, when I built my mkIII, I ended up with the windshield about 6" behind the leading edge of the center section. This is a very effect air scoop, dead air. Randy, at TNK, built me a fairing, but during finishing it ended up not fitting correctly. Another area of dead air is behind the doors in the area of both rear quarter windows. Brother Jim and I have talked about the fix for this many times, but never get around to doing it. We think a slat, similar to those used on the OH-58 (Bell Jet Ranger) would work on the sides, and a lexan or sheet metal fairing to kill the hole between the windshield and leading edge of the center section would fix that area of drag. How much more cruise speed would it give us? Don't know, but would be bound to improve some. I lost 5 mph top end installing the 8" Maule Tundra Tail Wheel, but I don't want to give it up because it works so well on the ground. Has tapered roller bearings in the pivot and lasts much longer than the bushed pivots. Oh well, I am happy with an 80 mph cruise. That has not changed. If I am patient, I eventually get every where I want to go. Good work guys, john h mkIII ________________________________ Message 4 _____________________________________ Time: 08:08:56 AM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: weight question Patrick: The reason I asked was, never flown any Kolb that gave any warning of an im pending stall except the airspeed indicator. They go into the mush with no warning, except ASI, and by this time you are stalling. Maybe some VG equipped Kolbs give a prestall buffet, similar to a Cessna. I don't know. The only Kolb I flew with VG's gave no warning. Seemed to s tall like all the other Kolbs. john h mkIII it is just a note of the speed at which the plane shakes to tell you to drop the nose a tad or you wil stall. It is just one of the boxes that nee ds ticking for the annual check. No idea what use is made of the information. I suppose if you had a plane which gave no warning of an incipient stall it would be worth knowing. Pat ________________________________ Message 5 _____________________________________ Time: 09:12:16 AM PST US Subject: Kolb-List: Re: weight question From: "JetPilot" I don't feel a prestall buffet in my Kolb, even with VG's. The stall is very hard to make happen, the AOA has to be ridiculously high, but when it gets to just below 30 MPH, the stall just happens, the nose drops a bit, and its flying again almost immediately. Everything is smooth and controls are effective before and throughout the stall. I have only stalled my Kolb power off, with power, the nose would be so high a stall would become an aerobatic maneuver. Mike -------- "NO FEAR" - If you have no fear you did not go as fast as you could have !!! Kolb MK-III Xtra, 912-S Read this topic online here: http://forums.matronics.com/viewtopic.php?p=231824#231824 ________________________________ Message 6 _____________________________________ Time: 10:25:41 AM PST US From: "Jack B. Hart" Subject: Kolb-List: FireFly Stall Pre-Buffet Kolbers, Before I offset the thrust line, the FireFly would stall/mush straight ahead. After I lowered and offset the thrust line to get more air over the horizontal tail surfaces and to center the ball without a tab on the rudder, things changed. The thrust line has been moved to the left. This gives the left wing a little more lift than the right. At idle and pulling the stick slowly back the FireFly right wing will buffet lightly and then falls off to the right. With power on, the buffeting is much more pronounced. It gives an early warning, to not pull the stick further back. If you do, it will continue to buck with increasing amplitude until the right wing stalls continuously and over you go. This is the disadvantage of an off set thrust line to trim out the FireFly at cruise. Use of a rudder trim tab instead of offset thrust line would solve this problem. Jack B. Hart FF004 Winchester, IN ________________________________ Message 7 _____________________________________ Time: 03:21:10 PM PST US From: "pj.ladd" Subject: Re: Kolb-List: Re: weight question never flown any Kolb that gave any warning of an impending stall>> Hi John, you are quite right as usual. My Xtra just mushes at the approach of a stall. I have never mistreated it badly enough to suddenly fall into a full stall and I suspect I would have to be very hamhanded to make it do so. However the annual check form is not only designed for Kolbs but for the full range of microlights, light aircraft, vintage aircraft and kit planes which the LAA oversees on behalf of the CAA. If I don`t put something in the box they will send it back. I am a bit surprised that your plane when fully loaded with all your long distance gear doesn`t sharpen up the usual mush into a `proper` stall. Just shows well Homers wing performs, a real weight lifter. Cheers Pat ________________________________ Message 8 _____________________________________ Time: 03:49:37 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: weight question Patrick: Another reason why I put so much faith in this old bird to get me there and get me home. Yes, Homer's wing is a "real" weight lifter. john h mkIII I am a bit surprised that your plane when fully loaded with all your lon g distance gear doesn`t sharpen up the usual mush into a `proper` stall. J ust shows well Homers wing performs, a real weight lifter. Cheers Pat ________________________________ Message 9 _____________________________________ Time: 07:33:31 PM PST US Subject: Kolb-List: Re: xtra wingtip mods From: "icrashrc" John, Thanks for the words of wisdom. Sometimes we forget how much of a test pilot the was required as the earlier designs evolved. I'm sure you now know the reason your first mass balances were ineffective was because of the inboard mounting position. That allowed the LE tube to act as a spring and could have well made the problem worse instead of better. We used your current mass balances for a start on weight needed. I calculated the weight of yours, added a fudge factor, and sized ours to be a little heavier. I'll be able to drill out some of the lead if i need to after the ailerons are covered and painted. I'll add more info on the center section in the next day or two. I have Paul writing that up for me. It's been a pain in the rear but we both think it will work out well. You're right about the area behind the doors. Getting the air to turn there would, if nothing else, help feed air to the bottom half of the prop. Clean air to the prop it always good! We may look at trying something it that area ourselves but not until after the plane is finished and flying. 5mph from just the tail-wheel is a lot! -------- Scott www.ill-EagleAviation.com do not archive Read this topic online here: http://forums.matronics.com/viewtopic.php?p=231955#231955 ________________________________ Message 10 ____________________________________ Time: 07:52:54 PM PST US From: "John Hauck" Subject: Re: Kolb-List: Re: xtra wingtip mods > 5mph from just the tail-wheel is a lot! > > -------- > Scott Indicated airspeed. May be like me, getting old and unreliable. ;-) It is a rather large tail wheel compared to the first one I had on this mkIII. It was the same as what I had on my original Firestar. The snowmobile bogey wheel. Didn't last long though. Went through a lot of tailwheels until I hit on the present one. Took Maule that long to design and produce something that would last me more than a year or two, back when I was flying a bit. john h mkIII ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message kolb-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Kolb-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/kolb-list Browse Digests http://www.matronics.com/digest/kolb-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.