---------------------------------------------------------- Kolb-List Digest Archive --- Total Messages Posted Tue 03/18/14: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:50 AM - Re: For Sale Ultrastar with trailer, $5500 (Mcabbage) 2. 09:13 AM - Re: Re: Drag Reduction Paradox (Jack B. Hart) 3. 09:40 AM - Re: Re: For Sale Ultrastar with trailer, $5500 (Dana Hague) 4. 03:31 PM - Re: Re: Drag Reduction Paradox (John Hauck) ________________________________ Message 1 _____________________________________ Time: 07:50:44 AM PST US Subject: Kolb-List: Re: For Sale Ultrastar with trailer, $5500 From: "Mcabbage" Hi Dana Mike Cabbage here hope all is well with Stan and yourself! Any idea what your next aerial adventure will be? Im still flying ppg but I bought a Kolb firestar 2 last fall and hope to get that in the air next summer. good luck selling your plane. Mike Read this topic online here: http://forums.matronics.com/viewtopic.php?p=420546#420546 ________________________________ Message 2 _____________________________________ Time: 09:13:48 AM PST US From: "Jack B. Hart" Subject: RE: Kolb-List: Re: Drag Reduction Paradox John, There are other benefits from vortex generators other than increased low speed lift performance. The one benefit that may be of help to you is now they seem to tame or remove high speed wing twitchness and improve aileron effectiveness. With VGs you may be able to move your "sweet spot" to a higher speed and an increased comfort level. Jack B. Hart FF004 Winchester, IN .......................................... From: "John Hauck" Wonder how that relates to a Kolb? and what is "at speed" for a Kolb? Top speed in a Kolb in normally never comfortable. They were not designed for speed. I have a normal "sweet spot" cruise speed, and a "get to the next way point a little quicker" cruise speed. In my MKIII, anything over 90 mph starts to get uncomfortable and is wasting a lot of fuel. Normal cruise, 5,000 rpm, 912ULS, is 80 to 85. High cruise, 5,200 rpm 912ULS, is 85 to 90, depended on I am loaded. If your Kolb is getting a speed boost with VGs, I am happy for you. john h ________________________________ Message 3 _____________________________________ Time: 09:40:11 AM PST US From: Dana Hague Subject: Re: Kolb-List: Re: For Sale Ultrastar with trailer, $5500 Hi Mike, If I sell the Ultrastar I'm hoping to buy a Fisher 404 biplane that a friend of mine has but has never flown. I still have the ppgs, but haven't flown them since I got the Ultrastar, both need some work... hoping to get one of those flying this year as well. Dana Do not archive At 10:50 AM 3/18/2014, you wrote: > >Hi Dana >Mike Cabbage here hope all is well with Stan and yourself! Any idea what >your next aerial adventure will be? Im still flying ppg but I bought a >Kolb firestar 2 last fall and hope to get that in the air next summer. >good luck selling your plane. >Mike > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=420546#420546 > > -- A liberal is someone who feels a great debt to his fellow man, which debt he proposes to pay off with your money. ________________________________ Message 4 _____________________________________ Time: 03:31:52 PM PST US From: "John Hauck" Subject: RE: Kolb-List: Re: Drag Reduction Paradox Jack H/Kolbers: Thanks for that information. I don't really care to land any slower than I do without VGs, nor do I believe any improvement in cruise speed would be enough to go to the expense and effort to mount VGs, nor the inconvenience of having to work around them once mounted. I have hard enough time getting the MKIII washed and cleaned now without having to deal with all those little things sticking up on the wing and other places. As far as "taming and removing high speed wing twitchiness and improving aileron effectiveness", I have never flown a Kolb that had those particular problems. I believe one of the primary problems with higher cruise and top speed on Kolb aircraft, other than the Ultrastar which used a different engine mount system, is the engineering of the Lord Mount engine mount system. I have shared this before and will share this with you again. Some 27 years ago I did some experimenting with my original Kolb Firestar, quite by accident. Cannot remember why I had the Firestar tied down or why I was doing the engine run ups, but during this exercise I discovered how much the engine was raised in the rear and canted down and to the left, I believe, as the RPM was increased right up to full throttle. Up to a certain point all was well, then the automatic divergence of the thrust line started eating up most of the thrust being produced by the engine. The Lord mount density was whatever was being shipped with the original Firestar kits way back then. During my next test flight, at about 65 or 70 mph, I can't remember now, I hit a brick wall. The Firestar would fly no faster on this flight, although it had pegged 85 mph, WOT straight and level flight on previous flights. I was a little upset with my airplane and reduced power slowly. As I did, the aircraft started accelerating. As it accelerated, at this lower than WOT power setting, I slowly increased power and the Firestar continued to increase airspeed. To remedy this problem I got on the horn and talked to Little Mike at old Kolb Aircraft. Asked him to find the hardest Lord Mounts available and told him why I wanted them. Those hard Lord mounts fixed my problem. My MKIII has always had the hardest Lord mounts, but with 80 and 100 hp engines, that much thrust still kicks the thrust line off center. Once the Kolb gets to a certain amount of drag, the more power applied, the more the thrust line is diverted from inline with the airframe. I believe that is why I can fly to 88 mph at 5,200 rpm, but increased power to 5,500 rpm only pushes the MKIII to 95 mph. Of course there are other factors involved, but the offset thrust line is one of the major problems. If I want to go faster, I need an airplane built for speed. If I want to have a fun airplane that I can also make some incredibly long, exciting flights, I'll stick with an 80 mph cruise and my MKIII. The above is my opinion only, based on personal experience building, breaking, and flying Kolb aircraft for the past 30 years. Take care, john h mkIII Titus, Alabama There are other benefits from vortex generators other than increased low speed lift performance. The one benefit that may be of help to you is now they seem to tame or remove high speed wing twitchness and improve aileron effectiveness. With VGs you may be able to move your "sweet spot" to a higher speed and an increased comfort level. Jack B. Hart FF004 Winchester, IN ------------------------------------------------------------------------------------- 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.