Piper CHEROKEE ARCHER II Pilot Operating Handbook page 23

SECTION
I
GENERAL
PIPER AIRCRAFT CORPORATION
PA.2&I8I,
CHEROKEE ARCHER U
(D
Weight and Balance
Terminology
Reference
Datum
An imaginary vertical plane
from which all horizontal
distances
are
measured
for
balance purposes.
Station
A
location along the airplane
fuselage
usually given
in
terms
of
distance
from the
reference
datum.
Arm
The horizontal distance from the rcference datum
to
the center
of
gravity (C.G.) of
an
item.
Moment
The
product
of
the weight
of
an item multiplied
by its
arm.
(Moment divided
by a
constant
is
used
to
simplify
balance
calculations
by
reducing
the number of digits.)
Centerof
Gravity
The point at which an
airplane
would
balance
if
suspended.
Its
(C.G.)
distance
from the rcference 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'
I
Unusable
Fuel
Fuel
remaining
after
a
runout test has been completed in
accordance
with
governmental regulations.
Standard
Empty
Weight
lVeight
of a
standard airplane including unusable
fuel, full
operating fluids and
full
oil.
Basic
Empty
Weight
Standad empty
werght plus optional equipment.
Payload
Weight
of occupants, car8p and
baggaSp.
Useful
Load
Differenoe between talceoff weight, or ramp weight
if
applicable,
and basic
empty weight.
Maximum Ramp
lVeight
Maximum weight approved
for gound
maneuver.
(It
includes
weight
of
start, ta:ti and run up fuel.)
Maximum
Takeoff
Maximum weight approved
for
the start
of the takeoff run.
Weight
Maximum
Landing
Maximum weight approved
for
the
landing touchdown.
Weight
Maximum Zero
Fuel
Maximum weight exclusive of
usable
fuel.
Weight
ISSUED: Jl,rNE 18,1976
REFORT:
V&790
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