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Airplane Flying Handbook
Transition to Multiengine Airplanes
WEIGHT AND BALANCE

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Airplane Flying Handbook

Preface

Table of Contents

Chapter 1,Introduction to Flight Training
Chapter 2,Ground Operations
Chapter 3,Basic Flight Maneuvers
Chapter 4, Slow Flight, Stalls, and Spins
Chapter 5, Takeoff and Departure Climbs
Chapter 6, Ground Reference Maneuvers
Chapter 7, Airport Traffic Patterns
Chapter 8, Approaches and Landings
Chapter 9, Performance Maneuvers
Chapter 10, Night Operations
Chapter 11,Transition to Complex Airplanes
Chapter 12, Transition to Multiengine Airplanes
Chapter 13,Transition to Tailwheel Airplanes
Chapter 14, Transition to Turbo-propeller Powered Airplanes
Chapter 15,Transition to Jet Powered Airplanes
Chapter 16,Emergency Procedures

Glossary

Index

The major difference between the two formats
(GAMA and the old) is that basic empty weight
includes full oil, and licensed empty weight does not.
Oil must always be added to any weight and balance
utilizing a licensed empty weight.

When the airplane is placed in service, amended
weight and balance documents are prepared by appropriately
rated maintenance personnel to reflect changes
in installed equipment. The old weight and balance
documents are customarily marked "superseded" and
retained in the AFM/POH. Maintenance personnel are
under no regulatory obligation to utilize the GAMA
terminology, so weight and balance documents
subsequent to the original may use a variety of
terms. Pilots should use care to determine whether
or not oil has to be added to the weight and balance
calculations or if it is already included in the figures
provided.

The multiengine airplane is where most pilots
encounter the term "zero fuel weight" for the first time.
Not all multiengine airplanes have a zero fuel weight
limitation published in their AFM/POH, but many do.
Zero fuel weight is simply the maximum allowable
weight of the airplane and payload, assuming there is
no usable fuel on board. The actual airplane is not
devoid of fuel at the time of loading, of course. This is
merely a calculation that assumes it was. If a zero fuel
weight limitation is published, then all weight in
excess of that figure must consist of usable fuel. The
purpose of a zero fuel weight is to limit load forces on
the wing spars with heavy fuselage loads.

Assume a hypothetical multiengine airplane with the
following weights and capacities:
Basic empty weight . . . . . . . . . . . . . . . . .3,200 lb.
Zero fuel weight . . . . . . . . . . . . . . . . . . . .4,400 lb.
Maximum takeoff weight . . . . . . . . . . . . .5,200 lb.
Maximum usable fuel . . . . . . . . . . . . . . . .180 gal.

1. Calculate the useful load:
Maximum takeoff weight . . . . . . . . . . . . .5,200 lb.
Basic empty weight . . . . . . . . . . . . . . . . .-3,200 lb.
Useful load . . . . . . . . . . . . . . . . . . . . . . . .2,000 lb.
The useful load is the maximum combination of usable
fuel, passengers, baggage, and cargo that the airplane
is capable of carrying.

2. Calculate the payload:
Zero fuel weight . . . . . . . . . . . . . . . . . . . . 4,400 lb.
Basic empty weight . . . . . . . . . . . . . . . . . -3,200 lb.
Payload . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,200 lb.

The payload is the maximum combination of passengers,
baggage, and cargo that the airplane is capable
of carrying. A zero fuel weight, if published, is the
limiting weight.

3. Calculate the fuel capacity at maximum payload
(1,200 lb.):
Maximum takeoff weight . . . . . . . . . . . . .5,200 lb.
Zero fuel weight . . . . . . . . . . . . . . . . . . .-4,400 lb.
Fuel allowed . . . . . . . . . . . . . . . . . . . . . . . .800 lb.

Assuming maximum payload, the only weight permitted
in excess of the zero fuel weight must consist of
usable fuel. In this case, 133.3 gallons.

4. Calculate the payload at maximum fuel capacity
(180 gal.):
Basic empty weight . . . . . . . . . . . . . . . . .3,200 lb.
Maximum usable fuel . . . . . . . . . . . . . . .+1,080 lb.
Weight with max. fuel . . . . . . . . . . . . . . .4,280 lb.
Maximum takeoff weight . . . . . . . . . . . . .5,200 lb.
Weight with max. fuel . . . . . . . . . . . . . . .-4,280 lb.
Payload allowed . . . . . . . . . . . . . . . . . . . . .920 lb.

Assuming maximum fuel, the payload is the difference
between the weight of the fueled airplane and the maximum
takeoff weight.

Some multiengine airplanes have a ramp weight,
which is in excess of the maximum takeoff weight. The
ramp weight is an allowance for fuel that would be
burned during taxi and runup, permitting a takeoff at
full maximum takeoff weight. The airplane must
weigh no more than maximum takeoff weight at the
beginning of the takeoff roll.

A maximum landing weight is a limitation against
landing at a weight in excess of the published value.
This requires preflight planning of fuel burn to ensure
that the airplane weight upon arrival at destination will
be at or below the maximum landing weight. In the
event of an emergency requiring an immediate landing,
the pilot should recognize that the structural
margins designed into the airplane are not fully
available when over landing weight. An overweight
landing inspection may be advisable—the service
manual or manufacturer should be consulted.

 

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