Island / Remote Destination Fuel Planner
No-alternate-nearby planning: the fuel a remote destination demands when the nearest divert is far — island rules, computed for any aircraft.
The island rule: when the alternate is far, the divert leg dominates the fuel plan — and 'destination weather is fine' is not a reason to skip it, because the runway can close for a disabled aircraft as easily as for fog.
Formula
⚠️ For flight planning and education only — verify with your POH/AFM and official sources. Not for primary navigation or in-flight emergency decision-making without POH data.
No-alternate-nearby planning: the fuel a remote destination demands when the nearest divert is far — island rules, computed for any aircraft.
About Island / Remote Destination Fuel Planner
Flying to an island — literal or figurative (any strip whose neighbors are far) — inverts normal fuel planning: the diversion leg, not the trip, sizes the tanks. This planner stacks the full requirement — trip fuel with wind, the destination-to-alternate leg, a hold-and-approach buffer for the sorting-out period, and the untouchable final reserve — and prints the breakdown, because seeing the divert leg's share is what cures the 'weather's fine, why carry it?' instinct.
How to use Island / Remote Destination Fuel Planner
- 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 fuel = trip + (destination→alternate) + hold/approach + final reserve — the island stack substituted step by step.
- 4Adjust inputs (or flip the unit toggle) until the scenario matches yours, then copy or share the result.
Why use Island / Remote Destination Fuel Planner?
- ✓Instant, free and private — every calculation runs in your browser, nothing is uploaded
- ✓Built on the published formula fuel = trip + (destination→alternate) + hold/approach + final reserve — the island stack with sources cited on the page
- ✓The island rule: when the alternate is far, the divert leg dominates the fuel plan — and 'destination weather is fine' is not a reason to skip it, because the runway can close for a disabled aircraft as easily as for fog.
- ✓Switch units, tweak any input and watch every result update live
Frequently asked questions
Why carry alternate fuel when the destination forecast is perfect?+
Because weather is only one closure mode: a gear-up ahead of you closes the only runway for hours; a fuel spill, a medevac priority, a wildlife strike inspection — none forecastable. On the mainland the next airport is 15 minutes away and the risk is invisible; on an island the SAME events strand you airborne. The alternate fuel is insurance against the runway, not the sky.
What makes a 'usable' alternate for this planning?+
Reachable at your degraded-case speed, weather above YOUR minimums at arrival time (not just legal mins), long and equipped enough for your aircraft, with fuel if the plan requires continuing — and genuinely open (island alternates have operating hours and NOTAM habits worth reading twice). A theoretical alternate that fails any test is mainland thinking wearing island clothes.
How do ICAO's isolated-aerodrome rules handle no-alternate cases?+
Where no alternate exists (true oceanic islands), Annex 6 substitutes additional holding fuel — typically two hours at the destination — converting 'divert capability' into 'wait-out capability.' The logic transfers to GA: if your remote strip truly has no reachable neighbor, the buffer input in this tool should grow toward wait-out-the-problem size, and the go/no-go weather discipline tightens correspondingly.
Should the divert leg use still-air or wind-corrected speed?+
This tool deliberately uses still-air TAS for the divert: at planning time you can't know which direction the diversion flies relative to the wind (the alternate bearing vs wind is event-dependent), and still-air splits the difference conservatively for moderate winds. For strong forecast winds, run the worst case — divert leg fully into the wind — and let the tanks answer for it.
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