Mechanical advantage is equal to the ratio of a force or resistance
overcome by the application of a lesser force or effort through a
simple machine. Gain in force is obtained at the expense of loss in
The rate at which mechanical advantage is produced by
hydraulic means is in direct proportion to the ratio of the size of
the smaller (input) area to the size of the larger (output) area.
Some hydraulic components, like shock struts and accumulators,
Atmospheric air and pure nitrogen are the only gases authorized for
use in Army aircraft.
Only mineral-base hydraulic fluids are authorized for use in aircraft
hydraulic systems. Operational fluid MIL-H-83282 is replacing MIL-H-
Care must be taken to ensure no contamination is allowed to enter the
Hydraulic fluids are quite flammable and must be
handled and stored with the same precautions as other POL products.