FAA Advisory Circular 43.13-1B
Acceptable Methods, Techniques, and Practices
Aircraft Inspection and Repair
AC 43.13-1B | 10. Weight and Balance | 1. Terminology | 10-2. Terminology
AC43.13-1B CHG 1
9/27/01
g. Arm (or Moment Arm). The arm (or
moment arm) is the horizontal distance in
inches from the datum to the c.g. of an item.
The algebraic sign is plus ( + ) if measured aft
of the datum, and minus ( - ) if measured for-
ward of the datum. Examples of plus and mi-
nus arms are shown in figure 10-2.
FIGURE 10-1. Typical datum locations.
Page 10-2
Par 10-2