If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Long wing twisting
I survived an unexpected twisting of my ASH-25 wing a few years back.
The situation was as follows; speed 145 knots, altitude 50 feet (finish line). After receiving my "Good Finish JJ", I initiated a climbing left turn to exchange speed for altitude, about 30 degrees nose up and banked 45 degrees left to reverse my track, to land on the ramp 1/2 mile behind me. To my surprise the ship kept rolling left. I applied full right aileron and rudder and it stopped rolling left, but fill right control input didn't make the ship roll back to level flight. As I climbed and speed decayed, my right turn command eventually became effective and the ship rolled out to level flight. The next day I spoke to the fellow that was on the finish gate. He said the inboard portion of my wing was bent up in the normal high speed bow, but my left wing tip was bent down. He said my wing looked like a sine wave! Why did this happen? I believe the left wing tip dug in as I applied left turn control at high speed. The aileron input caused the outboard section of the left wing to twist (L/E down) resulting in the tip digging in and giving me much more roll than I had commanded. Why did I survive? Because I was in a climb and my airspeed was decreasing. As speed decayed, the wing un-twisted and normal control was restored. Had this happened from level flight, I believe the wing twist (digging in) would have quickly resulted in a nose down attitude and I don't believe it would be possiable to recover from this situation. The wing tip is dug in and causing an un-commanded roll which will shortly cause the nose to drop resulting in even more speed. Opposite aileron won't (can't) make it roll out and back stick won't (can't) make it slow down, it will only tighten the spiral dive. After this experience I placed a personal maximum speed on the ship of 120 knots and was careful to limit my aileron input to about 50% of full throw at that speed. I told the new owner about my experience and recommended he adopt these limits. Is this what happened to Ivans and Egan? JJ Sinclair |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Announcing THE book on airshow flying | Dudley Henriques | Piloting | 11 | January 9th 04 07:33 PM |
Tyvek material for wing covers | Eric Greenwell | Soaring | 2 | October 18th 03 04:51 AM |
Props and Wing Warping... was soaring vs. flaping | Wright1902Glider | Home Built | 0 | September 29th 03 03:40 PM |
Across Nevada and Part Way Back (long) | Marry Daniel or David Grah | Soaring | 18 | July 30th 03 08:52 PM |
Wing Extensions | Jay | Home Built | 22 | July 27th 03 12:23 PM |