R
EVISION
:
-
D
ATE
:
12/29/04
P
AGE
:
2
Copyright
2004 Glasair Aviation, LLC Arlington, Washington All rights reserved
5-1 GENERAL DATA
W A R N I N G
To operate the Sportsman safely, it must be flown within the
specified center of gravity (CG) limits. These limits must be
strictly
observed. Flight in either a nose-heavy or a tail-heavy
airplane is unsafe and can result in loss of control.
Because every Sportsman is different, you must determine the CG for
your
airplane in both empty and loaded configurations in order to
establish safe loading criteria. What follows are some general
definitions and data useful in calculating the CG of your airplane. The
specific steps required are detailed below.
5-1.1 G
ENERAL
D
EFINITIONS
Arm (or Moment Arm)
— the horizontal distance in inches from the
datum to the center of gravity of a particular item.
Center of Gravity (CG)
— the point at which an object would balance if
suspended in space. The CG of a particular part of the airplane or
its load is typically expressed as a horizontal distance from the
datum, while the CG of the aircraft as a whole is expressed as a
percentage of the mean aerodynamic chord (see below).
CG Arm
— The arm obtained by adding the airplane’s individual
moments and dividing the sum by the total weight.
CG Limits
— The extreme center of gravity locations within which the
airplane must be operated at a given weight.