eVTOL Reserve Energy Margin Calculator

Quantify whether an eVTOL battery can satisfy mission, reserve, and contingency obligations under current operating assumptions.

Net energy available after accounting for depth-of-discharge limits.
Blend vertical segments, cruise, and contingency hover into a representative average.
Gate-to-gate mission duration including climb and approach.
Minimum reserve required by aviation authority or company policy.
Defaults to 10% if blank, covering reroutes or holding.

For preliminary electric flight planning only; confirm compliance with aviation authority approvals and aircraft flight manuals.

Examples

  • Usable capacity 180 kWh, average power 260 kW, mission 20 minutes, reserve 10 minutes, contingency 15% ⇒ Total required 143.00 kWh, margin 37.00 kWh (20.56% of capacity).
  • Usable capacity 120 kWh, average power 220 kW, mission 16 minutes, reserve 8 minutes, default contingency ⇒ Total required 93.87 kWh, margin 26.13 kWh (21.78% of capacity).

FAQ

Can I use different power levels for reserve segments?

If reserve energy assumes a different power draw, adjust the average power input to reflect that mix or split the analysis into mission and reserve segments before summing.

How do I handle battery degradation over time?

Reduce the usable capacity input to the end-of-life value mandated by your maintenance program so the reported margin already reflects degradation.

Does the tool support IFR reserve rules?

Yes. Set the reserve minutes to the regulatory requirement for IFR or VFR missions and adjust contingency percentage for additional holding fuel equivalents.

Additional Information

  • Result unit: kilowatt-hours available after satisfying required energy buffers.
  • Contingency defaults to 10% when left blank, aligning with typical advanced air mobility concepts of operations.
  • Average power draw should reflect combined hover, climb, cruise, and descent segments weighted by time.

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