Piper Cherokee Archer II Pilot Operating Handbook page 92

PIPER AIRCRAFT CORPORATION
PA-28-181, CHEROKEE ARCHER 11
6.1 GENERAL
SECTION 6
WEIGHT AND BALANCE
SECTION 6
WEIGHT AI'IlD BALANCE
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In order to achieve the performance and flying characteristics which are designed into the airplane,
it
must be flown with the weight and center of gravity (CG.) position within the approved operating range
(envelope). Although the airplane offers flexibility ofloading. it cannot be flown with the maximum number of
adult passengers. full fuel tanks and maximum baggage. With the flexibility comes responsibility. the pilot
must ensure that the airplane is loaded within the loading envelope before he makes a takeoff.
Misloading carries consequences for any aircraft. An overloaded airplane will not take off, climb or
cruise as well as a properly loaded one. The heavier the airplane is loaded. the less climb performance it will
have.
Center of gravity is a determining factor in flight characteristics. If the CG. is too far forward in any
airplane. it may be difficult to rotate for takeoff or landing. If the CG. is too far aft. the airplane may rotate
prematurcly on takeoff or tend to pitch up during climb. Longitudinal stability will be reduced. This can lead
to inadvertent stalls and even spins. and spin recovery becomes more difficult as the center of gravity moves aft
of the approved limit.
A properly loaded airplane. however. will perform as intended. Before the airplane is licensed. a basic
empty weight and CG. location is computed (basic empty weight consists of the standard empty weight of the
airplane plus the optional equipment). Using the basic empty weight and CG. location. the pilot can determine
the weight and CG. position for the loaded airplane by computing the total weight and moment and then
determining whether they are within the approved envelope.
The basic empty weight and CG. location are recorded in the Weight and Balance Data Form (Figure
6-5) and the Weight and Balance Record (Figure
6-7).
The current values should always be used. Whenever
new equipment is added or any modification work is done. the mechanic responsible for the work is required to
compute a new basic empty weight and CG. position and to write these in the Aircraft Log Book and the
Weight and Balance Rec0rd. The owner should make sure that it is done.
A weight and balance calculation is necessary in determining how much fuel or baggage can be boarded
so as to keep within allowable limits. Check calculations prior to adding fuel to insure against improper
loading.
The following pages are forms used in weighing an airplane and in computing basic empty weight. CG.
position. and useful load. Note that the ",-seful load includes usable fuel. baggage. cargo and passengers.
Following this is the method for computing takeoff weight and CG.
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ISSUED: JUNE 18, 1976
REVISED: MARCH
30,
1984
REPORT: VB-790
6-1