This Information Sheet covers current gear design
practices as they are applied to air vehicles and
spacecraft. The material included goes beyond the
design of gear meshes per se, and presents, for the
consideration of the designer, the broad spectrum of
factors which combine to produce a working gear
system, whether it be a power transmission or special
purpose mechanism. Although avariety of gear
types, such as wormgears, face gears and various
proprietary tooth forms are used in aerospace applications,
this document covers only conventional
spur, helical, and bevel gears.
1.1 Application
The working environment of the aerospace gear
has become so diverse that a single set of guidelines
will no longer suffice. The operating conditions
imposed on a high speed, high powered, transmission
or actuator are quite different than those experienced
by the spacecraft mechanism which must
function in a hard vacuum for long periods of time
without maintenance. This Information Sheet addresses
these differences and provides guidance to
the designer for these demanding applications.