UH-4 Commuter/Weight and Balance
SECTION 5. WEIGHT AND BALANCE
1 WEIGHT AND CG LIMITS
The weight and CG limits for this aircraft are:
| Max Gross Weight: | 1600 lb |
| Max Forward CG: | 70 inches |
| Max Aft CG: | 77 inches |
2 EMPTY WEIGHT AND CG
The empty weight and CG of this aircraft are:
| Empty Weight: | 900 lbs |
| Empty Aircraft CG: | 78.4 in |
| Empty Moment: | 70560 lb-in |
3 CG ARM DATA
The following arm data can be used to calculate moment at each of these stations.
| Pilot | 52.3 in (1.34 m) |
| Fuel | 94.4 in (2.42 m) |
4 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 6 pounds per gallon of 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.
As an example, consider a 180 lb pilot, a 160 lb passenger and 20 gallons of fuel. Weight of the fuel will be 20*6=120 lb.
| Item | Weight | Arm | Moment |
|---|---|---|---|
| Aircraft | 900 | 78.4 | 70,560 |
| Pilot | 180 | 52.3 | 9,414 |
| Co-Pilot | 160 | 52.3 | 8,368 |
| Fuel | 120 | 94.7 | 14,160 |
| Total | 1390 | x | 102,502 |
The final CG is calculated by dividing the total moment 102502 by the total weight 1390 yielding 73.7 inches. Cross checking the total weight and CG with the weight/CG limits indicates the aircraft is within limits. The "CG" is also calculated and displayed on the main menu for convenience.
