H-34 Choctaw/Weight and Balance
SECTION 5. WEIGHT AND BALANCE
Contents
1 General
The helicopter must be flown within the weight and CG (Center of Gravity) limits as specified in this section. Failure to adhere to these limitations will result in unpredictable performance. CG is measured in inches aft of the datum plane. The datum plane is located at the forward most point at the tip of the pitot tubes.
2 WEIGHT AND CG LIMITS
The weight and extreme CG limits for this aircraft are:
| Item | Limit |
|---|---|
| Max Gross Weight: | 14,400 lb |
| Max Forward CG: | 235 inches |
| Max Aft CG: | 251 inches |
Not withstanding the maxmimum limits shown above, the helicopter should only be operated within the weight vs CG envelope shown in .
3 EMPTY WEIGHT AND CG
The empty weight and CG of this aircraft are:
| Item | Limit |
|---|---|
| Empty Weight: | 7,645 lb |
| Empty Aircraft CG: | 167.7in |
| Empty Moment: | 3.21 M-lb-in |
4 CG ARM DATA
The following arm data can be used to calculate moment at each of these stations.
| Item | Limit |
|---|---|
| Pilot/Co-Pilot | 73 in (1.85 m) |
| Winch | 136 in (3.46 m) |
| RDF Operator | 145 in (3.68 m) |
| Hoist Operator | 150 in (3.82 m) |
| Utility Seat #1 | 243 in (6.17 m) |
| Fuel | 262 in (6.67 m) |
| Hook | 264 in (6.72 m) |
| Utility Seat #2 | 269 in (6.83 m) |
| Utility Seat #3 | 295 in (7.50 m) |
| Utility Seat #4 | 320 in (8.12 m) |
| Litter/Stokes Basket | 345 (8.78 m) |
| Ramp | 458 (11.63 m) |
5 WEIGHT AND CG CALCULATION
Total weight is calculated by adding total weight of empty aircraft, fuel, passengers and baggage. Fuel weight can be calculated assuming 7 pounds per gallon of (Jet-A) fuel. The CG is obtained by dividing total moment by total weight. Moment at each station is obtained by multiplying the arm of that station by the weight at that station. Total moment is obtained by adding moment for each station and the moment for the empty aircraft.
