Here is some info on the crash. This is the link to this article starts at page 7 for this accident.
Four unrelated incidents The accident aircraft is a highly modified de Havilland aircraft. In this case a Caribou had been converted to turbine power and was operated under the EXPERIMENTAL category of CAR 4b. The conversion was accomplished at Gimli, and the aircraft first flew in mid-November 1991, before accumulating about 23 hours on 12 flights by month end. These preliminary tests revealed the need for the replacement of the aircraft’s mechanical vacuum pumps with a Bendix suction system, the addition of in-line fuel boost pumps and the installation of a newly designed hydraulic pump. The accident occurred on August 27, 1992 on the first of several planned trips to flight check the fuel and hydraulic systems. The aircraft had been hangared in a partially disassembled
state over the winter, and had only recently been re-assembled, including the
Re-installation of the complete tail section. I.ll let the video show you what happened, and I will caution you right now that this footage is extremely graphic.
The accident investigation used this videotape and some 35mm photographs as a key resource in determining what went wrong at Gimli. With the exception of a slightly higher-than-normal nose attitude at lift-off, the aircraft’s initial climb appeared normal. At about 35 feet AGL, the aircraft made a noticeable pitchup movement. When I tell you that the photography revealed that the elevator control surfaces were observed to pitch trailing-edge-up for rotation, neutralize and then remain in the neutral position through the balance of that short flight, I expect most of you will come to the same conclusion as the Transportation Safety Board of Canada. The aircraft’s control gust locks were at least partly engaged. A very close examination of the video does indicate rudder movement and minimal elevator movement, during the start of the takeoff roll.
On the standard Caribou, the gust lock control handle is located forward of the power quadrant, and it has two positions. Forward for Unlocked, and aft for Locked. If the control surfaces are not in the neutral position when the lock is engaged, any movement of the surfaces through the neutral position will cause the lock to engage. In addition, on the factory-standard Caribou, the control handle is designed so that when it is in the aft-Locked position, the power levers cannot be fully advanced. This is intended to prevent power application and takeoff when the gust lock system is engaged. The accident investigation further revealed that the aircraft’s takeoff distance was approximately 20 per cent longer than anticipated for the conditions. This may provide further evidence that the gust locks played a part in this event. Analysis of the recovered debris indicated that, although the aileron and elevator locking mechanisms were in their respective disengaged positions, the rudder locking mechanism was found to have been in the fully engaged position at impact. Further investigation revealed that in fact, it had been jammed there by the forces of the impact. In addition, the analysis determined from the damage evidence that the aileron control lock had been dis-engaged at the time of impact. In its synopsis of the accident, the Transportation Safety Board concluded that the control gust lock system had not been fully disengaged prior to flight and that one or more of the locking pins had become re-engaged after lift-off.
What could have prevented this accident? The most obvious solution was that a complete six-point control check prior to takeoff would have revealed that free and proper movement of the control system was compromised.
