lml@lancaironline.net Mailing List Archive

<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Ernest Kovacs wrote: > I was wondering if the two recent IV-P accidents were caused by two very > experienced and competent pilots worrying too much about saving the airplane > rather than themselves. Let me start by saying that with only limited facts available, a lot of what I am saying about the accidents is conjecture. I am starting my analysis after the engine failure and do not want to get into the discussion of why/how the engine failed. The engine failure is a given. In the first accident, it appears that the pilot got killed because he did not have his shoulder harness on. People who have witnessed the accident scene have stated that with a shoulder harness, it was a very survivable accident. If that is true, then the pilot did the right things and got the plane to a survivable controlled crash. Because of other reasons he did not survive the survivable accident. The second accident appears to be a classic "return to the runway after engine failure on takeoff" scenario. This is a common killer because pilots generally grossly underestimate the altitude needed to transition from a climb attitude to a landing attitude, make a 270 degree turn (a 180 degree turn will put you parallel to the runway) and land. When most pilots start that maneuver, the firmly believe that they can make it based on their experience of doing 180 degree turns routinely. I have talked to one experienced test pilot who survived that maneuver (just barely -- he was lucky). The pilot said that he firmly believed, based on what he saw out the window, that he could make it back to the runway. The plane, fully insured by his maintenance shop's business insurance, was totaled and the pilot came very close to being totaled himself. If you can get anything from that accident, it is to practice that maneuver. At a safe altitude, put the plane in a takeoff attitude and speed, kill the engine and see how many feet it takes you to turn 180 degrees. After that try the same maneuver over a landmark (like a runway or a road) and see what it takes to get back to the road. Then add a couple of hundred feet to account for the surprise factor and having to perform under stress. That is how much altitude it will take for you to return the runway you just departed from. You can get away with slightly less altitude if there is a parallel runway or taxiway or a properly situated crossing runway. Remember that as you tighten the turn to steeper and steeper angles, the airplane will stall at higher and higher airspeeds. At those altitudes recovery from a stall is not possible. And a stall at those altitudes is likely to be 100% fatal. Now for a commercial plug. Products like Jim's AOA can warn you about impending stall. Products like Sierra Flight Systems' EFIS2000 can do the same and give you a gliding range corrected for airspeed and turns, which will tell you if you can make it back to the runway. But neither of them would substitute for practice and good judgment. Hamid >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://www.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>