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is approximate , because it does not take into account the deformation of the
tires or the possible weight shift of the operator . But experiments in the
McKinley case demonstrated that the tilt would occur between 18 and 20
degrees .
The accident occurs as the operator enters a terrain where the ground
slopes suddenly to one side . The manual recommends ' that to avoid the flipover , the operator should lean uphill . This is actually not too difficult to understand or to do if there is sufficient time to assess the problem . 10
ver
is particularly difficult , however , if the terrain changes suddenly and if
this is combined with a requirement to turn the vehicle .
Turning
Figure 5 illustrates the ATC 110 in a full ( 90 degree ) left hand turn .
The minimum turning radius for the ATC 110 ( shown on the drawing ) is 1 . 9
meters . Applying this , the angle at which the front wheel is rotated for the
sharpest possible turn is a shade over 30 degrees . ( See Figure 5 ) .
Figure 6 illustrates the centrifugal forces that will be acting
separately on man and machine ( see top view ) .
The actual force is in each
case proportional to the mass of the object ( vehicle or man ) , to the square of
the speed , and inversely to the turning radius .
In the lower right hand
corner the effects of the weight forces and the centrifugal forces are shown .
It is evident that the weight forces w tend to stabilize , while the
centrifugal forces F tend to turn the vehicle over with respect to the tilt
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