Air Navigation · Mass & Balance
Weight & Balance
An aircraft loaded outside its CG envelope can be uncontrollable. Mass and balance is examined in the Navigation paper and checked before every flight.
lb
lb
lb
gal
228 lb at 6 lb per US gallon
StatusWithin limitsWeight and CG inside the envelope
Cessna 172N-style trainer, normal category. Training example only.
Loading table
| Item | Weight (lb) | Arm (in) | Moment (lb-in) |
|---|---|---|---|
| Basic empty weight | 1,530 | 39.5 | 60,435 |
| Front seats | 340 | 37.0 | 12,580 |
| Rear seats | 0 | 73.0 | 0 |
| Baggage | 40 | 95.0 | 3,800 |
| Fuel (38 gal) | 228 | 48.0 | 10,944 |
| Total | 2,138 | 41.05 | 87,759 |
CG = total moment ÷ total weight = 87,759 ÷ 2,138 = 41.05 in
How to use it
- Load the seats, baggage and fuel.
- The loading table works out each moment the way the exam expects.
- The dot shows your weight and CG on the envelope; it turns red outside the limits.
For learning and exam practice only. Not for operational flight planning: always use your aircraft’s flight manual, official charts and current weather.