Aircraft Weight & Balance Calculator
Universal four-station weight & balance: enter your aircraft's empty weight/arm, loading and limits — get total weight, CG and an in/out-of-envelope verdict.
Defaults sketch a four-seat trainer — replace every number with your aircraft's actual W&B record values. Empty weight and arm differ airframe to airframe even within one model, and the forward limit usually slopes with weight.
Formula
⚠️ For planning and education only. Weight & balance must be computed from YOUR aircraft's actual empty weight, arm and current equipment list, and verified against the POH/AFM envelope before flight.
Universal four-station weight & balance: enter your aircraft's empty weight/arm, loading and limits — get total weight, CG and an in/out-of-envelope verdict.
About Aircraft Weight & Balance Calculator
Weight and balance is the preflight computation with the least forgiveness: an overweight airplane flies badly, but an out-of-CG one may not fly controllably at all. This calculator implements the universal moment method for a four-station light aircraft — every weight times its arm, summed, divided by total weight — with your own limits supplied, an explicit verdict, and the moment/1000 figure that matches how POH tables print it.
How to use Aircraft Weight & Balance Calculator
- 1Enter — sensible defaults are pre-filled so you see a worked result immediately.
- 2Read the live results: .
- 3Check the "With your numbers" line to see the formula CG = Σ(weight × arm) / Σ(weight); fuel: 6 lb per US gallon (avgas) substituted step by step.
- 4Adjust inputs (or flip the unit toggle) until the scenario matches yours, then copy or share the result.
Why use Aircraft Weight & Balance Calculator?
- ✓Instant, free and private — every calculation runs in your browser, nothing is uploaded
- ✓Built on the published formula CG = Σ(weight × arm) / Σ(weight); fuel: 6 lb per US gallon (avgas) with sources cited on the page
- ✓Defaults sketch a four-seat trainer — replace every number with your aircraft's actual W&B record values. Empty weight and arm differ airframe to airframe even within one model, and the forward limit usually slopes with weight.
- ✓Switch units, tweak any input and watch every result update live
Frequently asked questions
Where do I find my aircraft's empty weight and arm?+
In the aircraft's current weight & balance record — the amended sheet in the POH or aircraft file, updated after every equipment change. Never use another aircraft's numbers or a forum's 'typical' value: two same-year Skyhawks can differ by 40+ lb and an inch of arm after decades of avionics swaps.
Why is aft CG more dangerous than forward?+
Forward CG makes the aircraft nose-heavy: stable, higher stall speed, heavier flare forces — degraded but predictable. Aft CG erodes longitudinal stability itself: pitch becomes touchy, stalls flatten, and beyond the limit spin recovery may be aerodynamically impossible. Certification sets the aft limit against exactly that cliff.
Do I need to check landing weight and CG too?+
Yes — fuel burn moves both. Compute takeoff and a zero-or-landing-fuel case: if the fuel tank arm sits ahead of your loaded CG, burning fuel walks the CG aft through the flight, and a takeoff legally inside the envelope can land outside it. Our fuel-burn CG shift tool does this pair automatically.
Why does the forward limit change with weight on the POH chart?+
Elevator authority: the tail must lift the nose for flare and slow flight, and the heavier the aircraft, the less forward CG it can manage with the same tail. POH envelopes therefore slope the forward limit aft as weight increases. Enter the forward limit that applies at your computed weight — read it off the envelope chart.
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