Art asked: > Wish we knew what the shiny thing was they saw [departing the aircraft].
Art, Gary Pinnell did an unusually good job of reporting on the accident. I was so impressed I sent complimentary notes to his bosses. Google "Gary Pinnell ercoupe accident" for articles. One of the things mentioned in, I think, the preliminary report was that the majority of the inspection hole covers popped off the aircraft as well as the rear windows. As I recall, they did not pop off simultaneously but were strewn over a distance of the flight path. I'm sure the mechanic thought all was well with the aircraft. My otherwise excellent mechanic thought that about my Ercoupe even though the aileron tightness was out of spec. Fortunately, when I felt the beginning of my aileron flutter, I reacted almost instantly and correctly, loading the ailerons with a roll input to the yoke that stopped the beginning flutter before any damage was done. Heck, my mechanic at that time had done a full Ercoupe restoration as well as many years of Ercoupe annual inspections. But he did not know about Memorandums 56 and 57 I think. Service Memorandums 56 and 57 are NOT in a place that the average mechanic is going to find them during preparation for a normal annual inspection on an unfamiliar aircraft type. They are in the back of the Bulletins and Memorandums book. >From Gary Pinnell's story: http://tinyurl.com/ydf3qu8 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> "Another witness, who was also a certificated airline transport pilot, stated that while outside working on his house he observed the accident airplane flying overhead," Diaz wrote. "He estimated that the airplane was flying at an altitude of about 1,200 feet above ground level, and did not note anything abnormal about its flight path. About 45 minutes after first seeing the airplane, he heard an abnormal engine sound that diverted his attention again back to it." It sounded as if the engine was being "over-sped," the second unnamed witness told Diaz. It was as if the engine was at full power, and the airplane was in a high-speed dive. When the witness looked up, he saw the airplane pitching up and rolling into a steep left bank, and initially thought that the pilot was attempting to perform a "barrel-roll or a slow roll." >From the second witness's position, he could see both ailerons - the hinged flaps on the control surfaces attached to the wing's trailing edge - fluttering at a high frequency. . . . The second witness also reported to Diaz that during the breakup, the airplane released what looked like confetti, which he later determined to be painted chips from the airplane's fabric-covered wings. At Bartow Municipal Airport, 24 nautical miles west, the wind was blowing about 10 mph, and gusting to 16 mph. Portions of wreckage were found along a north-northeast 3,100 feet long path. Both aft cabin windows were found at the southern end of the wreckage path. Paint chips, inspection panels, and personal effects from inside the airplane were located further along. . . . "The first things that came off the plane were the cockpit back windows, which popped out, we'd guess, from vibration or distortion of their frame," said Burkhead, who viewed the NTSB report with fellow Ercoupe pilots. Inspection panels - aluminum discs - started popping from the bottom of the wings and were strewn along the remaining flight path. <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Does this sound like a simple main spar failure to any of you? I have nothing but guesses about the original cause of this failure. I have no idea if the pilot was doing a high speed pass or not. Nevertheless, if aileron flutter starts and you don't act instantly, you'd better be wearing a parachute and good luck even so. I even heard of a plane getting "vibration" at airspeeds as low as around 85. The aileron play was around one INCH! Fixing/replacing the control linkages and doing proper maintenance apparently fixed that plane as the test flight is said to have gone to 144 without problems. Make SURE your control surfaces are within spec! Ed
