AEROPRAKT-32 Pilot Operating Handbook
A32-240-POH
26
6.2 Computation of the CG position before flight
Before every flight pilot in command must make sure that the airplane takeoff weight and
CG are within the specified safe limits. The airplane CG position from datum (engine flange)
may be determined using the following formula:
𝑥
𝐶𝐺
=
𝑊
𝐴𝐸
× 𝑥
𝐶𝐺
𝑒𝑚𝑝𝑡𝑦
+ 𝑊
𝑐𝑟𝑒𝑤
× 𝑥
𝑐𝑟𝑒𝑤
+ 𝑊
𝑓𝑢𝑒𝑙
× 𝑥
𝑓𝑢𝑒𝑙
+ 𝑊
𝑏𝑎𝑔
× 𝑥
𝑏𝑎𝑔
𝑊
𝐴𝐸
+ 𝑊
𝑐𝑟𝑒𝑤
+ 𝑊
𝑓𝑢𝑒𝑙
+ 𝑊
𝑏𝑎𝑔
,
where:
𝑊
𝐴𝐸
– actual empty weight of the airplane;
𝑥
𝐶𝐺
𝑒𝑚𝑝𝑡𝑦
– CG position of the empty airplane;
𝑊
𝑐𝑟𝑒𝑤
– total weight of pilots;
𝑥
𝑐𝑟𝑒𝑤
= 1.663 𝑚
– position of pilots' CG;
𝑊
𝑓𝑢𝑒𝑙
– total weight of fuel in the tanks;
𝑥
𝑓𝑢𝑒𝑙
= 1. 60 𝑚
– position of fuel tank CG;
𝑊
𝑏𝑎𝑔
– weight of the baggage in the baggage container;
𝑥
𝑏𝑎𝑔
= 2.320 𝑚
– position of the baggage CG.
Computation must be performed in the same system of units: either kg-m or lb-in.
Note
: X
CG
must be between 1.529 m and 1.78 m (19% and 37% MAC) as shown in Fig. 2
The
sample
of the C.G. position calculation is provided in the table below:
Item
Weight, kg
× Arm, m = Moment, kg·m
Empty aircraft
305.0
× 1.620 =
494.1
Crew (2×65 kg)
130.0
× 1.663 =
216.2
Baggage
0.0
× 2.320 =
0.0
Fuel (20 l, 0.72 kg/l)
14.4
× 1.960 =
28.2
Total:
449.4
738.5
X
CG
= Total Moment / Total Weight = 1.643 m
