. ex : A320-200 Takeoff forward operational limits determination
Weight W kg Certified limit Operational margin kg.m Operational limit
CGcertified %RC H-armcertified m Moment kg.m Moment kg.m H-armoperational m CGoperationa l %RC
37320 15 18.431 686 168 -5 296.33 691 465 18.573 18.393
53000 15 18.431 976 818 982 114 18.530 17.383
63000 17 18.514 1 166 406 1 171 703 18.598 19.005
72000 17 18.514 1 333 036 1 338 333 18.588 18.754
73500 18.9 18.594 1 366 664 1 371 961 18.666 20.618
15% 17% 19% 21% Operational margin Moment WeightCertified forward limit Operational forward limit H-armCertified = (CGCertified x 0.041935) + 17.8015 MomentCertified = H-armCertified x Weight Moment0perational = MomentCertified . (-5 296.33) H-armoperational = Moment0perational / Weight CGoperational = (H armoperational . 17.8015) / 0.041935
The complete computation leads to the determination of each individual operational limit. 176
Getting to Grips with Aircraft Weight and Balance
C. BALANCE CHART DESIGN
In Flight limits Takeoff limits
Landing limits
Operational Limits On the balance chart the 3 operational limits . Takeoff, Landing and In-flight . are not represented because if the Takeoff CG position check against its corresponding limit can be done after a manual or computerized computation, the determination of the Landing CG and furthermore the In-flight CG positions on a paper document is much more difficult, it is hardly possible to check these CG positions against their corresponding CG limits.
So only a Takeoff limit is drawn on the Load and Trim Sheet, this takeoff limit is the more limiting one of the three operational limits, depending on the values of each operational margins.
Note often on A320 documents the forward In Flight limit is more limiting than the Takeoff one. And this specially for low aircraft weights. So the forward operational limit published on the balance chart or in the AHM560 is made of part of the In Flight limit and part of the Takeoff limit.
WEIGHT AND
BALANCE
WEIGHT AND
BALANCE
C. BALANCE CHART DESIGN
3.9. Zero Fuel limit determination
3.9.1. Definition of the Zero Fuel Limit
On the balance chart it is necessary to check the Takeoff CG position against the Takeoff
operational limit, this ensures that the aircraft CG position is within the certified takeoff limit.
Nevertheless this check is not sufficient to ensure that the aircraft CG remains within the in flight
and landing limits during the whole flight.
This second check cannot be made easily by checking the landing CG position and the different
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