Cessna 152 1978, Pilot Operating Handbook

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CESSNA AIRCRAFT COMPANY FOR TRAINING USE ONLY
MODEL 152 1-10
WEIGHT AND BALANCE TERMINOLOGY
Reference Datum Reference Datum is an imaginary vertical plane from which all horizontal
distances are measured for balance purposes.
Station Station is a location along the airplane fuselage given in terms of the
distance from the reference datum.
Arm Arm is the horizontal distance from the reference datum to the center of
gravity (C.G.) of an item.
Moment Moment is the product of the weight of an item multiplied by its arm.
(Moment divided by the constant 1000 is used in this handbook to simplify
balance calculations by reducing the number of digits.)
Center of Gravity
(C.G.)
Center of Gravity is the point at which an airplane, or equipment, would
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 Center of Gravity Arm is the arm obtained by adding the airplane’s
individual moments and dividing the sum by the total weight.
C.G. Limits Center of Gravity Limits are the extreme center of gravity locations within
which the airplane must be operated at a given weight.
Standard Empty
Weight
Standard Empty Weight is the weight of a standard airplane, including
unusable fuel, full operating fluids and full engine oil.
Basic Empty Weight
Basic Empty Weight
is the standard empty weight plus the weight of
optional equipment.
Useful Load Useful Load is the difference between takeoff weight and the basic empty
weight.
Gross (Loaded)
Weight
Gross (Loaded) Weight
is the loaded weight of the airplane.
Maximum Takeoff
Weight
Maximum Takeoff Weight is the maximum weight approved for the start of
the takeoff run.
Maximum Landing
Weight
Maximum Landing Weight is the maximum weight approved for the landing
touchdown.
Tare Tare is the weight of chocks, blocks, stands, etc. used when weighing an
airplane, and is included in the scale readings. Tare is deducted from the
scale reading to obtain the actual (net) airplane weight.