UniCarriers FD160-2 Operation & Maintenance Manual page 21

HOW THE LIFT TRUCK WORKS?
■ ACCELERATING, DECELERATING AND TURNING
The principle of inertia provides that a stationary object will remain
stationary as long as there is no external force acting on it, and
that a moving object will continue moving at a constant speed as
long as there is no external force acting on it.
Due to inertia, when the lift truck starts to move there is a
momentary backward force, and when it stops there is a
momentary forward force. As a result, if the brakes are applied
suddenly, there is a very strong hazard that the forward force will
become strong enough for the truck to tip forward.
Likewise, when the truck is turning there is a centrifugal force
that pulls it outward from the turning center. This force can cause
the truck to fall sideways. Since the zone of lateral stability is
especially narrow, it is necessary to slow down substantially when
turning in order to prevent the truck from tipping.
When the load is elevated the overall center of gravity is raised,
increasing the danger of the truck tipping over to the front or side.
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