Well, perhaps as Hartmut said "Maybe the pilot was still compensating for the non-existing tail position , e.g. pushing the yoke down on take off to get the tail up, but he then doubled the forces since the tail was already up and the steering was hard to do then".
This can cause additional drag as the pressure that the nose wheel perform on the ground increases when pushing the yoke forward ... perhaps a short grass field was the other reason why the pilot decided to abort the take off. Sorry, have no more details, just want to know if this could be a problem or could happen as may be a security issue. Daniel ________________________________ From: "[email protected]" <[email protected]> To: [email protected] Sent: Fri, April 30, 2010 8:58:33 PM Subject: Re: [ercoupe-tech] Raising the tail: Two more questions I don't understand why raising the tail would have on take off. If the Coupe took off with the tail low it will take off with the tail high, just apply back pressure on the stick and take off. When I fly many times I will do a short field take off anyway just to keep familiar. Lee Browning Thank you very much Ed ! Your answer is very clear, and I agree with you in that if the runway is so short that having a tail low Coupe instead of a correctly rigged Coupe makes a significant difference in safety, there is no margin left to operate out of that airfield and some change has to be made in the plane, as you said, or move to another airfield. Best regards Daniel Arditi ________________________________ From: Ed Burkhead <e...@edburkhead. com> To: ercoupe-tech@ yahoogroups. com Sent: Fri, April 30, 2010 7:57:05 PM Subject: RE: [ercoupe-tech] Raising the tail: Two more questions Daniel Arditi wrote: > For those who got accustomed in taking off and landing > with a "low tail" (especially during take off): Did you have > any problem or something to tell about the difference? > >I once heard that after rising the tail, and on a short grass > field the pilot had to abort a take off because he felt > uncomfortable as it was a bit hard to rotate in that same > field as he used to operate ? Daniel, Tail dragger aircraft drag their tails on the ground largely because that angle of attack is about right for absolute minimum speed liftoff. In other words, according to Wolfgang Langewiesche, author of “Stick and Rudder,” a tail dragger gear (called the “conventional” gear in antique days) is really a “takeoff” gear. A Coupe with a tail low condition is rolling down the runway part-way to being a taildragger and could, conceivably, lift off sooner than a properly rigged Coupe – as long as the crosswind is mild, otherwise the plane is in danger. When you lift off at that minimum airspeed, you have little reserve lift and a lull in the wind could drop you back to the runway in a bad way. Over many years, I was able to operate comfortably out of 1800 ft. grass runways (with no obstacles) and would sometimes accept a 1600 ft. grass runway if conditions were right. I found this in the worst configuration, 1400 pounds gross weight and tail at the normal height on a plane rigged with the 9˚ elevator up travel.: 1. The plane will pick up speed faster when it is level on the ground as the wings are at a low angle of attack presenting their lowest parasitic and induced drag. 2. When you are on a very short runway, as you get close to liftoff speed, you can use the elevator to raise the nose, lift off a couple of feet, lower the nose a bit and let the plane pick up speed in low ground effect. In low ground effect, you have no rolling friction from the ground or grass AND you have almost no induced drag as you are in close ground effect. So, you quickly pick up the extra few mph you need for a safe climb out at best angle or best rate of climb airspeed, your choice. This technique is especially important on long grass, muddy or rough air fields. 3. If the runway is so short that having a tail low Coupe instead of a correctly rigged Coupe makes a significant difference in safety, you do NOT have enough safety margin to be operating out of that airfield. Get an aggressive climb prop and/or a bigger engine and/or lighten you load considerably so you can change to a different airfield. Ed Ed Burkhead http://edburkhead/ Ercoupe/index. htm ed -at- edburkh???ead. com (change -at- to @ and remove ??? and spaces) _ ____________ _________ _________ _________ _________ _________ ___ Auto Insurance Quotes Enter Zip Code and Compare Rates! How Much Can You Save? EZRateQuotes. com
