Learn how to add fuel, set payload stations, check weight and centre of gravity, choose the right loader and fix common loading errors.
In Microsoft Flight Simulator, X-Plane, Prepar3D and most other flight simulators, add fuel and payload through the aircraft’s Weight and Balance menu or dedicated EFB/load manager. Enter fuel by tank, assign people and cargo to payload stations, apply the load, then verify total weight and centre of gravity before departure.
Which fuel and payload menu should I use?
Use the aircraft’s own EFB or load manager when it has one; otherwise, use the simulator’s standard Weight and Balance menu. A mistake we see constantly is loading an add-on through both systems, after which the aircraft’s custom code overwrites the simulator menu or counts part of the load twice.
| Loading method | Use it for | Main caution |
|---|---|---|
| Simulator Weight and Balance menu | Default and simpler aircraft | A complex add-on may override its values after loading |
| Aircraft EFB or load manager | Airliners and other systems-driven add-ons | Press the load or apply control and allow timed loading to finish |
| External ground-service controls | Aircraft with documented integration | Passenger or fuel-truck animation alone may not change aircraft mass |
How do I add the fuel and payload correctly?
The safest method is to plan the load, use one loading system and verify the resulting weight rather than trusting the entered figures alone.
- Plan the route and load. Establish the route and expected conditions before choosing fuel; our guide to building a simulator flight plan covers that first stage. Decide how many occupants, bags or cargo items the aircraft will carry.
- Calculate block fuel. Block fuel normally includes taxi fuel, trip fuel and the required reserves rather than just the amount expected to burn en route. Use our detailed method for calculating fuel and refuelling the aircraft if those figures are not already available.
- Park and prepare the aircraft. Apply the parking brake and use the gate, ramp or loading state expected by the aircraft. Some add-ons require engines off, doors open, chocks fitted or ground power connected before their loader will operate.
- Enter fuel in the correct units. Check whether the loader expects kilograms, pounds, US gallons, litres or a percentage of tank capacity. Distribute fuel according to the aircraft’s loading guidance and keep paired wing tanks balanced unless its procedure specifies otherwise.
- Assign payload to stations. Enter occupants, baggage and freight in the available seat rows, cabin zones, baggage compartments or cargo holds. If the loader offers automatic distribution, use it as a starting point and then inspect the centre-of-gravity indication.
- Apply the load and wait. Default aircraft may update instantly, while detailed add-ons can simulate boarding, cargo loading and refuelling over time. Do not begin performance calculations until loading has stopped.
- Verify the result. Compare the loader with the cockpit fuel indication or flight-management system. Confirm ramp weight, expected take-off weight and centre of gravity are within the displayed limits.
What counts as payload weight?
Payload means the people, baggage and freight carried by the aircraft; usable fuel is accounted for separately. Crew treatment varies: one aircraft may include crew in its operating empty weight, while another provides dedicated crew stations, so adding them twice produces an overweight aircraft.
For an airline-style calculation, operating empty weight plus payload gives zero fuel weight. Adding block fuel gives ramp weight; taxi burn then reduces that to take-off weight. Our explanation of zero fuel weight and its related limits shows how these figures connect.
Do not type the desired take-off weight into a payload field. Enter the real payload first, add the planned fuel separately and let the simulator calculate the resulting gross weight.
How do I keep the centre of gravity within limits?
Distribute payload between the available stations until the indicated centre of gravity sits inside the aircraft’s approved envelope. Total payload can be legal while its position is unsafe: placing every passenger in the rear seats or all baggage in one hold may push the aircraft outside its forward or aft limit.
In a light aircraft, check individual seats and baggage areas. In an airliner, check cabin zones and forward and aft holds. The same principle is demonstrated by our guide to how payload placement changes A320 ZFWCG.
Fuel distribution can also move the centre of gravity as tanks empty. If the aircraft provides predicted take-off and landing CG values, check both. Obtain the take-off trim setting only after the final payload and fuel load has been applied.
Why are my fuel or payload values not changing?
Most loading failures come from competing loaders, unapplied changes or mismatched units rather than a damaged aircraft file.
- The values snap back: the aircraft’s custom loader is overriding the simulator menu. Reload using only the EFB or aircraft load manager.
- Nothing happens: select the loader’s apply, start or load control and satisfy any requirement for engines off, parking brake, doors or chocks.
- The amount is far too high or low: check kilograms against pounds and mass against volume. A tank percentage represents capacity, not a planned fuel mass.
- The CG indication is red: move passengers or cargo between stations. Redistribution can correct balance, but it cannot fix an excessive total weight.
- The aircraft remains overweight: reduce payload or revise fuel within the requirements of the flight plan. Do not remove reserve fuel merely to force the figure below the limit.
- Visual boarding works but weight does not change: the ground-service animation may not be connected to the simulator’s flight model. Apply the figures through the aircraft loader instead.
- Fuel gauges disagree with the loader: allow timed refuelling or tank transfer to finish, then compare actual fuel mass rather than tank percentages.
When should fuel and payload be loaded?
Set fuel and payload after the route and expected load are known but before calculating take-off performance or setting trim. If either figure changes later, update the flight-management system’s ZFW or ZFWCG entries where required and calculate the performance again.
Most default simulators allow weight to be altered in flight, but doing so is unrealistic outside testing or a deliberately constructed scenario. Detailed aircraft may block the change or require fuel transfer and dumping systems to handle it properly.