>> A friend of mine did this with a small (30') tower on field day. When the
>> tower got down low it pulled the Jeep that it was attached to and slid the
>> wheels.
>> The tower swung out off center and crashed down. There is tremendous force
>> on the cable when the tower is near the ground.
The coefficient of static friction for rubber tires against wet asphalt can be
as low as .25
Depending on what the jeep was on (grass?) the horizontal resistance it would
provide at the key point in the lower, might only have been 1/5th it's weight.
Also, a jeep attach is too low. The best way to reduce the forces involved is
with a higher point for the pull somehow.
Rember that the pull force is not necessarily the highest force in the system
(think of the forces at the hinge).
So if you think the pull force is huge, think of the possibility of the system
breaking at the other points involved.
It depends on the exact pull setup.
-kevin
ad6z
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