Adel El Feky
Weight & Balance
Weight and Balance Definitions :
Airplane Basic Empty weight
Is the weight of :
y The structure .
y Powerplant .
y Furnishings .
y Unusable fuel .
y Engine and constant-speed drive system oil .
y Chemical toilet fluid .
y Basic emergency equipment .
y Fire extinguishers .
y Oxygen system .
y Buffet, bar and gallery structure .
y Electronic equipment required by the operator .
y Fluids which are contained in a closed system .
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Adel El Feky
Basic Operating Weights ( BOW )
Is the aircraft basic empty weight plus the following operational
items :
y Flight and cabin crew and their baggage .
y Manuals and navigational equipment .
y Food and beverage and related service equipment .
y Washing and drinking water; emergency equipment .
y Life rafts, life vests .
y Cargo handling system and related airborne equipment .
Maximum Design Zero Fuel Weight ( MZFW )
- Is the maximum airplane weight less usable fuel, engine
injection fluid.
- accordance with the applicable government regulations so that
the airplane structure and airworthiness requirements are not
exceeded .
Actual Zero Fuel Weight ( ZFW )
Is the airplane basic operating weight plus the payload and must
never exceed the maximum design zero fuel weight .
Maximum Design Landing Weight ( MLW )
Is the maximum weight authorized at touchdown . This maximum
landing gross weight is a structural limitation .
Operational Landing Weight
- The maximum landing weight authorized at touchdown .
- The operational landing weight must never exceed the
maximum design landing weight .
Maximum Design Takeoff weight ( MTOW )
- Is the maximum weight authorized at takeoff brake release by
applicable government regulations and excludes taxi and run-
up fuel .
- This weight is limited by the structural limitations of the
airplane .
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Adel El Feky
Operational Takeoff Weight
- Is the maximum weight authorized at takeoff brake release must
never exceed the maximum design takeoff weight .
Maximum Design Taxi weight
- Is the maximum weight authorized for ground maneuver by the
applicable structural limitations and includes taxi and run-up
fuel .
Gross Weight
- Is the weight of an airplane after all items have been added .
Payload
- Consists of the total weight of the revenue producing passengers,
passenger baggage, and/or cargo .
Useful Load
Consists of the payload, usable fuel, and engine injection fluid .
Datum Line
- Is an imaginary reference line from which all calculations or
measurements are taken for weight and balance .
- The datum line on the airplane's nose .
- On some jet aircraft, the datum line may be forward of the
airplane's nose .
Body Station Numbers
- The numbers represent the number of inches that the particular
location is aft of the datum line .
Moment Arm
- The horizontal distance from the center of gravity of an object
to the datum line .
Moment
- Is the tendency, to produce rotation about a point or axis .
- can be determined by multiplying the weight of a mass by its
horizontal distance from the datum line .
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Adel El Feky
Center Of Gravity
- Is the point in an aircraft around which all weight is evenly
distributed or balanced .
Empty Weight Center Of Gravity
- Is the center of gravity of the airplane in an empty weight
condition .
Mean Aerodynamic Chord ( MAC )
- Is the chord of a section of imaginary aerofoil on the wing .
- Is a value used in engineering and weight and balance
calculations .
Leading Edge Mean Aerodynamic Chord ( LEMAC )
- Is the distance in inches from the datum line to the leading edge .
Trailing Edge Mean Aerodynamic Chord ( TEMAC )
- Is the distance in inches from the datum line to the training edge .
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