What remains the same
Both platforms require the same basic information: aircraft variant, takeoff weight, CG, flap configuration, runway, surface condition, temperature, pressure and wind. V1, VR, V2 and FLEX retain the same conceptual roles.
This web calculator uses the same transparent input workflow for both simulators, making it useful as an independent estimate or learning aid.
Where simulator results can differ
Each add-on developer can choose different aerodynamic models, engine data, weight limits and performance tables. Some aircraft contain a built-in EFB calculator; others expect manual external planning. Weather sources and update times can also differ.
As a result, two apparently identical departures may produce slightly different speeds or FLEX temperatures. Larger discrepancies usually indicate a variant, unit, runway or weather mismatch.
- Flight-model and engine implementation
- Aircraft loading and CG calculation
- Built-in EFB or MCDU logic
- Weather source and report time
- Supported runway-performance detail
Workflow in Microsoft Flight Simulator
MSFS aircraft may use the simulator EFB, an add-on tablet or manual MCDU entry. Collect the final loaded weight and CG after the aircraft is configured, then compare the external estimate with any built-in result.
Workflow in X-Plane
X-Plane add-ons often provide their own loading interface and may use plugin-specific performance systems. Read weight and CG from the active aircraft rather than copying numbers from an unrelated planning profile.
How to handle conflicting results
First confirm the same aircraft and engine variant, units, weight definition, runway intersection, surface condition and weather. Then compare configuration assumptions such as packs and anti-ice. Prefer the aircraft developer’s documented system when it uses add-on-specific performance data.
This calculator remains intentionally platform-neutral and is not a replacement for certified or developer-provided data.