Mass and balance
Weights times arms, the flight manual way. Load the aeroplane and see the take-off and landing points on the centre of gravity envelope, with how much fuel the load leaves room for.
Aeroplane
Warrior II POH (VB-1180) section 6: 2,440 lb version. Utility category: 2,020 lb, no rear passengers or baggage. Datum: 78.4 in forward of the wing leading edge at the inboard intersection of the straight and tapered sections.
Loading
Fuel weighs 131 kg at 6 lb per US gallon. With this load you can carry up to 182 L and stay at or below the 1,107 kg maximum take-off weight.
Result
| Condition | Weight | CG | Limits |
|---|---|---|---|
| Zero fuel | 835 kg | 84.9 in ✓ | 83.0 to 93.0 in |
| Take-off | 965 kg | 86.3 in ✓ | 84.9 to 93.0 in |
| Landing | 938 kg | 86.0 in ✓ | 84.3 to 93.0 in |
Within limits at take-off and landing, and inside the normal category envelope throughout.
Working: weights, arms and moments
| Item | lb | Arm in | Moment in·lb |
|---|---|---|---|
| Basic empty weight | 1,500 | 85.9 | 128,850 |
| Pilot and front passenger | 340 | 80.5 | 27,370 |
| Rear passengers | 0 | 118.1 | 0 |
| Baggage | 0 | 142.8 | 0 |
| Fuel (48 US gal) | 288 | 95.0 | 27,360 |
| Take-off | 2,128 | 86.3 | 183,580 |
CG = total moment ÷ total weight. The POH may quote moments divided by 100 or 1,000; the answer is the same.
Arms and envelopes from the flight manual's loading section; your own aircraft's weighing schedule gives the basic empty weight and arm, which vary between airframes and after any modification. Take-off weight feeds the take-off and landing tool. Theory in mass and balance in the Aircraft Technical guide.