FYI, Just got this from an old squadron buddy:
This seems to fit.
The following, I believe is a fairly accurate analysis of Leeland's loss of control of the P51 Galloping Ghost. It was written in a blog of comments.
This accident was caused by the failure of the left elevator trim tab. This exact same failure occurred to the P-51 Voodoo in the 1998 Reno race. That aircraft didn't roll inverted, but climbed up past 9,000 feet, where the pilot woke up.
… Voodoo very abruptly pulled up; however, Hannah didn’t radio a distress call. … Steve Hinton flew over to take a look Voodoo. “You OK Bob?” called Hinton. “Yea, this thing just popped big time,” replied Hannah. What Hannah didn’t mention is that the g-load from the quick pull-up had caused him to black out. He finally managed to reach the throttle and reduced Voodoo’s power. At that point Hannah radioed that he “(wasn’t) out of it yet,” but he wasn’t thinking clearly. Later, he declared a mayday and made a perfect landing. … On the ground one could see what cause Voodoo’s problems during the race. The left elevator torque tube failed when the elevator trim fluttered and departed the plane. Fortunately, Bob Hannah’s skill and coolness in the cockpit saved day.
When the trim tab fell off Voodoo, the plane shot upwards and the 10G deceleration force caused Bob Hannah to black out entirely. That’s just as you would expect: the faster you go, the more the plane points upwards on its own, and the more you need to point the nose down to trim the airplane. Thus, at speed and level, the trim tab points up relative to the airflow over the elevator, causing the elevator to be deflected slightly down to maintain level flight.
At over 500 miles per hour, there are enormous airloads on the elevator trim tab to keep the elevator in a position that allows the pilot to maintain control, making damage to the trim tab more likely. Remove the trim tab and the non-trimmed elevator settings immediately deflect up, just like when pulling the stick back hard. That’s what causes the abrupt climb (and corresponding loss of consciousness) when the trim tab falls off.
Hannah regained consciousness at 9,000 feet and, as you can tell from the above, took some time to come back to his senses. It was even the same trim tab. The difference between Voodoo’s close call and Galloping Ghost’s tragedy may have been pure, dumb luck: Voodoo didn’t roll after losing the trim tab while Galloping Ghost did.
But that doesn’t necessarily mean flutter caused the trim tab to dislodge, or that the trim tab was the cause of the accident, or that the trim tab was the only cause of the accident. It’s quite possible something else caused the Galloping Ghost to climb rapidly, and in that process the flutter developed or the trim tab was damaged. As has been reported, some members of the crowd noticed “a strange gurgling engine noise” before Galloping Ghost pitched upwards. Further, as discussed below, it’s possible the trim tab failure could have been avoided, and more could have been done — such as ensuring the pilot was harnessed properly and plotting the race further from the stands — to prevent this tragedy.
Aircraft like the P-51 Galloping Ghost, require a great deal of nose down trim to offset the lift which tends to force the nose up at high speeds (450 mph in this case). This trim setting places a great deal of stress on the trim tab and its hinges and mounting. If the tab should fail, the elevator will return to neutral, inducing an extremely violent pitch-up with zero warning. The associated g forces can incapacitate a pilot....
Notice that in some photos that Mr. Leeland is not visible in the photo. In other photos, he is clearly slumped against the instrument panel. If he can't see out, he can't know where the aircraft is pointed. Leeland is obviously unconscious, due to GLOC. GLOC is an acronym for G induced Loss Of Consciousness.
Note also that the g loading was severe enough to overpower the hydraulic cylinder and extend the tail wheel.... My understanding is that it requires g loading in excess of 9g to do that. So, this is strong evidence that Leeland was subjected to g forces of at least 9g, and very likely higher than that. Any pilot, especially a 74-year old pilot, will GLOC under that loading. He was unconscious immediately after the pitch up and the aircraft went where it did due to factors like torque, aileron and rudder trim.
I believe that the NTSB will rule this accident a result of a catastrophic mechanical failure, probably resulting from undetected fatigue of the trim tab hardware and/or mounting structure.
This seems to fit.
The following, I believe is a fairly accurate analysis of Leeland's loss of control of the P51 Galloping Ghost. It was written in a blog of comments.
This accident was caused by the failure of the left elevator trim tab. This exact same failure occurred to the P-51 Voodoo in the 1998 Reno race. That aircraft didn't roll inverted, but climbed up past 9,000 feet, where the pilot woke up.
… Voodoo very abruptly pulled up; however, Hannah didn’t radio a distress call. … Steve Hinton flew over to take a look Voodoo. “You OK Bob?” called Hinton. “Yea, this thing just popped big time,” replied Hannah. What Hannah didn’t mention is that the g-load from the quick pull-up had caused him to black out. He finally managed to reach the throttle and reduced Voodoo’s power. At that point Hannah radioed that he “(wasn’t) out of it yet,” but he wasn’t thinking clearly. Later, he declared a mayday and made a perfect landing. … On the ground one could see what cause Voodoo’s problems during the race. The left elevator torque tube failed when the elevator trim fluttered and departed the plane. Fortunately, Bob Hannah’s skill and coolness in the cockpit saved day.
When the trim tab fell off Voodoo, the plane shot upwards and the 10G deceleration force caused Bob Hannah to black out entirely. That’s just as you would expect: the faster you go, the more the plane points upwards on its own, and the more you need to point the nose down to trim the airplane. Thus, at speed and level, the trim tab points up relative to the airflow over the elevator, causing the elevator to be deflected slightly down to maintain level flight.
At over 500 miles per hour, there are enormous airloads on the elevator trim tab to keep the elevator in a position that allows the pilot to maintain control, making damage to the trim tab more likely. Remove the trim tab and the non-trimmed elevator settings immediately deflect up, just like when pulling the stick back hard. That’s what causes the abrupt climb (and corresponding loss of consciousness) when the trim tab falls off.
Hannah regained consciousness at 9,000 feet and, as you can tell from the above, took some time to come back to his senses. It was even the same trim tab. The difference between Voodoo’s close call and Galloping Ghost’s tragedy may have been pure, dumb luck: Voodoo didn’t roll after losing the trim tab while Galloping Ghost did.
But that doesn’t necessarily mean flutter caused the trim tab to dislodge, or that the trim tab was the cause of the accident, or that the trim tab was the only cause of the accident. It’s quite possible something else caused the Galloping Ghost to climb rapidly, and in that process the flutter developed or the trim tab was damaged. As has been reported, some members of the crowd noticed “a strange gurgling engine noise” before Galloping Ghost pitched upwards. Further, as discussed below, it’s possible the trim tab failure could have been avoided, and more could have been done — such as ensuring the pilot was harnessed properly and plotting the race further from the stands — to prevent this tragedy.
Aircraft like the P-51 Galloping Ghost, require a great deal of nose down trim to offset the lift which tends to force the nose up at high speeds (450 mph in this case). This trim setting places a great deal of stress on the trim tab and its hinges and mounting. If the tab should fail, the elevator will return to neutral, inducing an extremely violent pitch-up with zero warning. The associated g forces can incapacitate a pilot....
Notice that in some photos that Mr. Leeland is not visible in the photo. In other photos, he is clearly slumped against the instrument panel. If he can't see out, he can't know where the aircraft is pointed. Leeland is obviously unconscious, due to GLOC. GLOC is an acronym for G induced Loss Of Consciousness.
Note also that the g loading was severe enough to overpower the hydraulic cylinder and extend the tail wheel.... My understanding is that it requires g loading in excess of 9g to do that. So, this is strong evidence that Leeland was subjected to g forces of at least 9g, and very likely higher than that. Any pilot, especially a 74-year old pilot, will GLOC under that loading. He was unconscious immediately after the pitch up and the aircraft went where it did due to factors like torque, aileron and rudder trim.
I believe that the NTSB will rule this accident a result of a catastrophic mechanical failure, probably resulting from undetected fatigue of the trim tab hardware and/or mounting structure.
Please, if you can give some details on what this 'driveshaft' drove and why. The plane that for sure had a driveshaft was the P39 Airacobra - mid engine fighter.
