Center of Gravity
The point at which an airplane would
(C.G.)
balance if suspended. Its distance from the
reference datum is found by dividing the
total moment by the total weight of the
airplane.
C.G. Arm
The arm obtained by adding the airplane’s
individual moments and dividing the sum
by the total weight.
C.G. Limits
The extreme center of gravity locations
within which the airplane must be operated
at a given weight.
Usable Fuel
Fuel available for flight planning.
Unusable Fuel
Fuel remaining after a runout test has been
completed in accordance with govern-
mental regulations.
Standard Empty
Weight of a standard airplane including
Weight
unusable fuel, full operating fluids and full
oil.
Basic Empty
Standard empty weight plus optional
Weight
equipment.
Payload
Weight of occupants, cargo and baggage.
Useful Load
Difference between takeoff weight, or
ramp weight if applicable, and basic empty
weight.
Maximum Ramp
Maximum weight approved for ground
Weight
maneuver. (It includes weight of start, taxi
and run up fuel.)
SECTION 1
PIPER AIRCRAFT CORPORATION
GENERAL
PA-38-112, TOMAHAWK
REPORT: 2126
ISSUED: JANUARY 20, 1978
1-10
Center of Gravity
The point at which an airplane would
(C.G.)
balance if suspended. Its distance from the
reference datum is found by dividing the
total moment by the total weight of the
airplane.
C.G. Arm
The arm obtained by adding the airplane’s
individual moments and dividing the sum
by the total weight.
C.G. Limits
The extreme center of gravity locations
within which the airplane must be operated
at a given weight.
Usable Fuel
Fuel available for flight planning.
Unusable Fuel
Fuel remaining after a runout test has been
completed in accordance with govern-
mental regulations.
Standard Empty
Weight of a standard airplane including
Weight
unusable fuel, full operating fluids and full
oil.
Basic Empty
Standard empty weight plus optional
Weight
equipment.
Payload
Weight of occupants, cargo and baggage.
Useful Load
Difference between takeoff weight, or
ramp weight if applicable, and basic empty
weight.
Maximum Ramp
Maximum weight approved for ground
Weight
maneuver. (It includes weight of start, taxi
and run up fuel.)
SECTION 1
PIPER AIRCRAFT CORPORATION
GENERAL
PA-38-112, TOMAHAWK
REPORT: 2126
ISSUED: JANUARY 20, 1978
1-10