I suspect the cause was severe aileron flutter followed by drastic maneuver followed by fabric separation then catastropic failure of the spar, followed by loss of wings. Bill
To: [email protected]; [email protected]; [email protected] From: [email protected] Date: Wed, 30 Sep 2009 12:16:51 +0100 Subject: Re: [ercoupe-tech] Re;FYI -Seibring crash Read & Ponder Was it aileron flutter he saw (and heard) or loose fabric? On 30/9/09 08:15, "Hartmut Beil" <[email protected]> wrote: Ralph. I have the same doubts about the eye witness account. It is almost impossible to see any detail of a plane that flies 1200 feet above you. Now, the plane might have been directly above the witness and maybe the sun was in an angle that mirrored. But the breakup occurred at 11:15 local time I think, ( If it would be Zulu time, the flight would have happened at 6 A.M in the morning), so at least the report. This is the worst time to see anything against the sky. Anyhow. Maybe he could see the detail. If both ailerons were to flutter, the whole control system was broken loose. What I believe is that the upper spar cap broke at one side and the whole wing was fluttering. That made the other side of the spar also loose its wing support and we now had two wings fluttering. THAT you can observe from 1200 ft below. I hope the NTSB will get the details out soon. So the talk "we don't do nothing, the controls were fluttering" will stop. Hartmut To: [email protected] From: [email protected] Date: Tue, 29 Sep 2009 17:44:53 -0700 Subject: RE: [ercoupe-tech] Re;FYI -Seibring crash Read & Ponder "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." Hard to believe. Eyewitness accounts are known to be unreliable. “And they flutter that much that a witness from 1200ft below can see them moving.” Even less reliable. 1200 feet away and he can see both fluttering? Ralph Finch ________________ Alon A2 A-188 G-HARY www.ercoupe.co.uk _________________________________________________________________ Insert movie times and more without leaving Hotmail®. http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutorial_QuickAdd_062009
