A planning estimate for electric UAS when representative average current or power data is available.
Start here
- Enter the battery voltage, capacity and representative propulsion load.
- Include auxiliary power, available energy, efficiency and the reserve you want to hold.
- Choose Calculate to compare available flight time and distance with your targets.
How to read the results
Read the reserve and target margins alongside endurance. Representative measured flight loads are more useful than motor maximum ratings.
Optional aircraft profile: Manual values
Electric UAS Flight Endurance Estimator
Planning output only. Verify assumptions and results against authoritative data, manufacturer information, approved procedures, test evidence and competent engineering or regulatory review before use.
Calculation basis
Nominal battery energy is converted to usable mission energy after the available-energy and reserve factors are applied. Average propulsion power is nominal voltage multiplied by representative average current; auxiliary power is then added. Endurance is mission energy divided by total average power.
Limitations and verification
- Valid only for electric systems and a representative average power condition.
- Does not model climb, hover, transition, wind, manoeuvre, thermal limits, battery voltage curve or reserve policy requirements.
- Use flight logs from the released configuration for operational planning.
Version and review status
Formula set: v1.2
Staging review date: 17 August 2026
Status: Staging beta pending user acceptance and cross-browser checks.
Using this calculator
A planning estimate for electric UAS when representative average current or power data is available.
Inputs and units
| Input | Unit or format |
|---|---|
| Battery capacity | mAh |
| Nominal voltage | V |
| Average propulsion current | A |
| Additional continuous load | W |
| Available battery energy | % |
| Operational reserve | % |
| Target mission duration | min |
Model and formula
Nominal energy (Wh) = capacity (mAh) / 1000 × voltage (V). Mission energy = nominal energy × available fraction × (1 − reserve fraction). Average power (W) = voltage × propulsion current + auxiliary power. Endurance (min) = 60 × mission energy / average power.
Worked example
For 10,000 mAh at 22.2 V, 20 A average propulsion current, 10 W auxiliary load, 80% available energy and 20% operational reserve, nominal energy is 222 Wh. Mission energy is 142.08 Wh, power is 454 W and estimated endurance is 18.8 minutes. Against a 20-minute target the margin is −1.2 minutes.
Interpreting the result
Reserve is held back from the available energy, not subtracted as percentage points from nameplate capacity. Use current from representative flight logs; a motor maximum is not an average mission load. A failed target check identifies an energy shortfall under the entered assumptions.
Limits and verification
- Valid only for electric systems and a representative average power condition.
- Does not model climb, hover, transition, wind, manoeuvre, thermal limits, battery voltage curve or reserve policy requirements.
- Use flight logs from the released configuration for operational planning.
Worked examples checked against the calculator source on . These are reproducible calculation checks, not aircraft trials, site measurements or operational approval. Existing formula versions and technical review status remain as stated above.