E cargo1aft +E cargo2aft +E cargo3 aft +E cargo4 aft +E cargo5 aft
Note : when an EDP system is used to compute the aircraft CG position and weight, then the cargo delta index may be determined for each individual cargo position, in this case the cargo distribution inaccuracy is nil.
WEIGHT AND
BALANCE
WEIGHT AND
BALANCE
C. BALANCE CHART DESIGN
144
C. BALANCE CHART DESIGN
. Ex: A320 bulk loading in the compartment 1.
Determination of the average H-arm of the compartment 1: Position
Maximum allowable H-arm
MOMENT (Bulk)
Weight (kg) (m)
(kg.m) (W x H) 11
1045 10.744
11227.5 12
1225 12.433
15230.4 13
1132 13.971
15815.2
∑=
3402 42273.1
H-armcargo1 = 12.426 m
FORWARD INACCURACY:
Position 11 is the only position in front of the average H-arm.
ECargo1 distribution fwd = W11 x (H11 . Hcargo1)
ECargo1 distribution fwd = 1045 x (10.744 . 12.426) = . 1757.7 kg.m
AFT INACCURACY:
Position 12 and 13 are aft of the average H-arm.
ECargo1 distribution aft = W12+13 x (H12+13 . Hcargo1) W12+13 = W12 + W13 = 1225 + 1132 = 2357kg H ×
W +
H ×
W 12.433 ×
1045 +
13.971×
1132
12 1213 13
H == =
14.260 m
12+
13
W +
W 1045 +
1132
12 13
ECargo1 distribution aft = 2357 x (14.260 . 12.426) = + 4322.7 kg.m
WEIGHT AND
BALANCE
WEIGHT AND
BALANCE
C. BALANCE CHART DESIGN C. BALANCE CHART DESIGN
. Cargo CG tolerance inaccuracy:
Eitem location = Witem x (H-armitem real . H-armitem assumed)
For this inaccuracy determination the different loading scenarios have to be studied. For each of them, Eitem location is determined with (H-armitem real . H-armitem assumed) being the allowed tolerance when loading a cargo position. Eitem CG tolerance = Witem x tolerance
This tolerance is described in the WBM for ULD loaded aircraft in section 1.10. For each ULD baseplate the CG is never right on the baseplate geometric center. The longitudinal allowance is equal to ±10% of the depth of the baseplate.
For, bulk loaded aircraft the same principle is considered.
The longitudinal allowance is equal to ±10% of the depth of the bulk position.
The process for checking the different configuration is the following : . Study each configuration separately (containers, pallets 88“, pallets96“ and/or Bulk) . For each configuration determine the total inaccuracy considering that the inaccuracy for each ULD/bulk position is independent from the other ones. E =
. Determine the configuration generating the highest inaccuracy.
WEIGHT AND
BALANCE
WEIGHT AND
BALANCE
C. BALANCE CHART DESIGN
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：Getting to Grips with Aircraft Weight and Balance(66)
