At 07:31 PM 2/11/99 -0800, you wrote: >'Coupers: > >I might as well put my 2 cents in too. My basic instruction >was in a two-control 'coupe on a grass field with perpetual >cross wind. I now have about 35 hours in my own >three-control Alon plus 1400 hours in Cessnas. > >My own technique for xwind landings is to treat the Alon as >a normal airplane and land straight ahead to minimize the >side load on the gear. An Alon benefit is that you can >deflect the ailerons into the wind while steering down the >runway. (Does that mean that a three-control coupe has an >even higher crosswind capability?) When an xwind is strong >enough you run out of rudder (thanks to spin-proofing) and >you end up landing crabbed which all on this list seem to >agree works well. I often land on one (upwind) wheel which >results in uncoordinated flight a foot or two above the >ground, but again results in the slowest touchdown speed and >least side load. > >There's no question in my mind about the trailing link gear >on a low-wing plane which due to geometry, also dumps lift >after touchdown, making landings very easy. I believe that >much of the talk about which way to hold the wheel on a >two-control coupe after touchdown is moot - you have to >steer down the runway and there is little actual deflection >of the wheel after touchdown, only pressure. At landing >speed, the wheel (and therefore the ailerons too) can't be >turned more than a few degrees from straight or you would be >steering into the weeds. > >Speaking of geometry and trigonometry, I've been trying to >come to grips with the 45 knot direct cross-wind claim. To >use a simple example with a 45 knot direct crosswind, if the >touchdown (actual hitting the runway) speed was 45 knots in >the direction of the runway, the indicated airspeed would be >1.4 x 45 = 63 knots (72.5 MPH) which is not far off what >some also claim to be a good touchdown speed. At that speed, >the crab angle would be 45 degrees. I maintain that >touchdown at a 45 degree crab angle would instantly collapse >the nosegear (if the mains didn't collapse first) as it >slammed down and the coupe would be reduced to a ball of >aluminum. If landed slower, the crab angle would be even >more extreme. Can anyone find fault with the above trig? > >I'm not knocking the coupe. I LIKE flying and landing it. I >just worry about novices trying something dangerous after >reading anecdotal data. If anyone can point me to the >certification document which claims a very high crosswind >component, I'd like to see it (and like to meet the person >who demonstrated it to the FAA).
Dave, As one of the 2 individuals who has indeed landed in a 45 kt direct X-wind let me tell you that this is defiantly not a BS story nor an exaggeration. The wind speed is reported as what the wind speed indicator in the FBO was reading. I would say your calculations are probably right but can also say that the noes gear ever felt as though it would collapse. Since we both had held off as long as we could our touch down attitude was nose high. As the trailing link gear swings you around you will be making contact with the ground with the nose gear but you will not have full weight on it yet. In the particular landing in question I was in trail about 200' behind (I know this may sound too close but under the circumstances seemed like a mile apart and placed neither plane in a potential for collision). The lead coupe is a 2 control, my Forney is a 3 control which gave me the ability to combine a slip with the crab. There is just not enough rudder to just slip. Needless to say my landing was not nearly as hairy as the lead's. His upwind wing did lift for a moment, enough to have the main on that side about 1 foot off the ground, I had a real good view of this. Also since a Forney has the split tail I was able to further reduce my touchdown speed over the lead's. This is not anecdotal data and I do state this is not something to be tried lightly but in an emergency is doable, and since we were low on fuel we considered it preferable to landing in a pasture somewhere. Our real mistake was in not just landing directly across the runway. It was 100' wide so with 45 kts on the nose could have been done without much trouble. This is what we did on takeoff and we were off in 75'
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