Aircraft Loading Form
Use aircraft-specific empty weight, moment, arms, and limit data. Default values are editable planning placeholders.
Station Moment Table
This table helps you audit each station before checking the final envelope.
| Station | Weight lb | Arm in | Moment lb-in |
|---|---|---|---|
| Basic Empty Aircraft | 1,663.00 | 39.50 | 65,688.50 |
| Front Seats | 170.00 | 37.00 | 6,290.00 |
| Rear Seats | 0.00 | 73.00 | 0.00 |
| Fuel at Ramp | 240.00 | 48.00 | 11,520.00 |
| Baggage Area 1 | 20.00 | 95.00 | 1,900.00 |
| Baggage Area 2 | 0.00 | 123.00 | 0.00 |
| Optional Item | 0.00 | 90.00 | 0.00 |
Example Data Table
| Item | Example Weight | Example Arm | Example Moment |
|---|---|---|---|
| Basic empty aircraft | 1,663 lb | 39.50 in | 65,688.50 lb-in |
| Front seats | 340 lb | 37.00 in | 12,580.00 lb-in |
| Fuel | 240 lb | 48.00 in | 11,520.00 lb-in |
| Baggage Area 1 | 20 lb | 95.00 in | 1,900.00 lb-in |
Formula Used
Moment: Moment = Weight × Arm
Total weight: Total Weight = Sum of all station weights
Total moment: Total Moment = Sum of all station moments
Center of gravity: CG = Total Moment ÷ Total Weight
Takeoff weight: Ramp Weight − Taxi Fuel Weight
Landing weight: Takeoff Weight − Trip Fuel Burn Weight
Forward limit interpolation: Forward CG = Low Arm + Ratio × Arm Change
How to Use This Calculator
Enter the aircraft basic empty weight and arm from the current weight record. Add pilot, passenger, baggage, optional item, and fuel details. Enter real station arms from the approved aircraft data. Adjust the ramp, takeoff, landing, baggage, and CG envelope limits. Press the calculate button. Review warnings first. Then compare ramp, takeoff, and landing conditions against the plotted envelope. Download CSV or PDF for planning records.
Weight and Balance Planning for a Cessna 172S
Why Balance Matters
Weight and balance is a core physics check. It connects force, distance, and rotational effect. The aircraft weight acts through its center of gravity. Each load creates a moment around a reference datum. A safe loading plan keeps the center of gravity inside the approved envelope.
How the Calculator Works
This calculator uses the standard arm and moment method. You enter each station weight. You also enter the distance of that station from the datum. The tool multiplies weight by arm. It then adds all moments and all weights. The final center of gravity is total moment divided by total weight.
Ramp, Takeoff, and Landing Checks
Ramp weight includes fuel before taxi. Takeoff weight removes taxi fuel. Landing weight removes taxi and planned trip fuel burn. These three conditions can have different center of gravity values. Fuel is usually located near a fixed station. Burning fuel removes both weight and moment. This can move the balance point.
Envelope Review
The chart plots the editable loading envelope. It also plots ramp, takeoff, and landing points. A point inside the envelope suggests the entered load is acceptable. A point outside the envelope needs correction. You may reduce baggage, move load forward, reduce fuel, or change passenger placement.
Important Safety Note
This page is a planning aid only. Aircraft records can differ by equipment, serial number, modification, and weighing history. Use the current aircraft weight sheet and approved operating handbook. Do not use placeholder values for dispatch. A pilot must confirm all limits before flight.
FAQs
1. What is aircraft center of gravity?
It is the balance point of the loaded aircraft. It is found by dividing total moment by total weight. Safe flight requires it to stay within approved limits.
2. Why does fuel burn affect balance?
Fuel has weight and moment. As fuel burns, both are removed from the aircraft. This may shift the center of gravity during flight.
3. Can I use the default arms for flight?
No. Default arms are editable placeholders. Use the current aircraft weight record and approved operating handbook for real flight planning.
4. What does moment mean?
Moment is weight multiplied by arm. It measures the turning effect of a load around the aircraft datum.
5. What happens if CG is too far aft?
An aft center of gravity can reduce stability and make recovery harder. It may also affect stall and control behavior.
6. What happens if CG is too far forward?
A forward center of gravity can increase control force. It may reduce elevator authority during takeoff, landing, or flare.
7. Why check ramp and takeoff separately?
Ramp weight includes fuel used during taxi. Takeoff weight removes taxi fuel. Some aircraft have a small difference between these limits.
8. Is this calculator a legal dispatch document?
No. It is only a planning tool. Always use approved aircraft documents, current weighing data, and required operating procedures.