Arrow PA-28R-201 Pilot's Operating Handbook And Faa Approved Airplane Flight Manual page 20

SECTION I
GENERAL
PIPER AIRCRAFT CORPORATION
·PA·28R-20., ARROW
1.19 SYMBOLS, ABBREVIATIONS, AND TERMINOLOGY (continued)
(f) Weight and Balance Terminology
(
Reference Datum
Station
Arm
Moment
Center of Gravity
(CG.)
C.G. Arm
c.G. Limits
Usable Fuel
Unusable Fuel
Standard Empty
Weight
REPORT: VB-1365
1-10
An imaginary vertical plane from which all
horizontal distances are measured for
balance purposes.
A location along the airplane fuselage
usually given in terms of distance from the
reference datum.
The horizontal distance from the reference
datum to the center of gravity (C.G.) of an
item.
The product of the weight of an item multi-
plied by its arm. (Moment divided by a
constant is used to simplify balance calcu-
lations by reducing the number of digits.)
The point at which an airplane would (
balance if suspended. Its distance from the
reference datum is found by dividing the
total moment by the total weight of the
airplane.
The arm obtained by adding the airplane'S
individual moments and dividing the sum
by the total weight.
The extreme center of gravity locations
within which the airplane must be operated
at a given weight.
Fuel available for flight planning.
Fuel remaining after a runout test has been
completed in accordance with govern-
mental regulations. (
Weight of a standard airplane including
unusable fuel, full operating fluids and full
oil.
ISSUED: SEPTEMBER 15, 1988