Analysis of a scooter tow accident
http://www.youtube.com/watch?v=RWM0yIh3_mw
1. The pilot in the video appears to be a "new" or "beginner" student. I have no
direct knowledge of how much experience the student has. But I make this
observation based on the following:
A. The pilot doesn't hold up the glider on the outside of the shoulders, but
rather on their neck. I would expect that a more experienced pilot would have
been taught how to hold the glider.
B. The pilot is being towed in the instructor's version of a training situation,
i.e. they are not towed up to get a soaring flight.
If I am correct then this is a student that needs to be carefully handled by the
scooter tow operator to be sure that the student is safe, no matter what
mistakes the student is likely to make.
2. The student is pulled too high. He should not be more than five feet off the
ground (measured from his feet). He appears to be at times twenty to thirty feet
off the ground. He is high enough to cause real damage to himself when things go
wrong. And that is exactly what happens.
3. It is apparently the case that the student is required to release from the
tow line (see comments from student in the video). The student should not be
required to release. The tow operator is in charge and they should put the
student on the ground long before they are required to release. Students should
not be concerned with releasing at all until they have had plenty of practice
towing.
4. The tow operator should always put the student on the ground by at least
three quarters of the way to the turn around pulley. When the student is three
to five feet off the ground this is quite easy to do. When the student is twenty
to thirty feet off the ground it is more problematic. The tow operator should
never pull the student to the turn around pulley as was apparently true in this
case. Comments on the video indicate that the scooter motor was running as the
student made a 180 degree turn near the turn around pulley.
5. The student is off the ground for approximately eight five seconds. Assuming
twenty mph air speed (near stall) this means that the turn around pulley was
approximately 2,500' away from the scooter tow operator. It would be quite
difficult for the tow operator to see what was going on with the student pilot
2,000+ feet away from him. He would not be able to see that the student wasn't
able to release, if that was the case. It appears as though the turn around
pulley is set too far away for a safe low and slow student instruction scooter
tow operation.
6. At about the thirty ninth second into the video it is possible to see that
the tow is taking place in windy conditions. Students should not be towed in
windy conditions.
http://OzReport.com/1313156142
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