Stability and Center of Gravity
The center of gravity (CG) of any object is
the single point about which the object is
balanced in all directions. Every object
has a CG. When the lift truck picks up a
load, the truck and load have a new com-
bined CG. The stability of the lift truck is
determined by the location of its CG, or if
the truck is loaded, the combined CG.
A.
CG LOAD
B.
CG TRUCK
C.
COMBINED CG
The lift truck has moving parts and therefore has a CG that
moves. The CG moves forward and back as the mast is til-
ted forward and back. The CG moves up and down as
mast moves up and down. The CG moves left and right as
the traverse frame moves left and right.
A.
CG LOAD
B.
COMBINED CG
C.
CG TRUCK
The center of gravity, and therefore the stability of the loa-
ded lift truck, is affected by a number of factors, such as
size, weight, shape, and position of the load; the height to
which the load is raised; tire pressure; and the dynamic
forces created when the truck is moving.
These dynamic forces are caused by things like accelera-
tion, braking, turning, and operating on uneven surfaces or
Operating Procedures
80
Property of American Airlines