{
  "slug": "fuel-endurance-range",
  "title": "Fuel Endurance & Range Calculator",
  "heading": "Fuel Endurance and Range Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/fuel-endurance-range",
  "summary": "Max flight time and still-air range from usable fuel and burn rate.",
  "description": "Endurance and range planning is where fuel exhaustion accidents get made, almost always by pilots who used total fuel capacity instead of usable fuel, or ignored the reserve requirement. This tool takes usable fuel (not total, since unusable fuel sits below the pickup and can't be counted), subtracts your required reserve (45 minutes day VFR, 30 minutes night VFR under most interpretations, more for IFR), and converts the remaining burnable fuel into both flight time and still-air distance at your planned true airspeed.",
  "formula": "Usable fuel time = (usable gallons ÷ burn rate) − reserve time. Range = usable fuel time × true airspeed.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=fuel-endurance-range",
  "inputs": [
    {
      "id": "usableFuel",
      "label": "Usable fuel",
      "kind": "number",
      "hint": null,
      "default": 50,
      "unit": "gal",
      "min": 1,
      "max": null
    },
    {
      "id": "burnRate",
      "label": "Fuel burn rate",
      "kind": "number",
      "hint": null,
      "default": 10,
      "unit": "gal/hr",
      "min": 0.5,
      "max": null
    },
    {
      "id": "tas",
      "label": "True airspeed",
      "kind": "number",
      "hint": null,
      "default": 120,
      "unit": "kt",
      "min": 10,
      "max": null
    },
    {
      "id": "windComponent",
      "label": "Headwind (negative for tailwind)",
      "kind": "number",
      "hint": null,
      "default": 10,
      "unit": "kt",
      "min": -50,
      "max": 100
    },
    {
      "id": "reserveMin",
      "label": "Required reserve",
      "kind": "number",
      "hint": null,
      "default": 45,
      "unit": "min",
      "min": 0,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "usableEnduranceHr",
      "label": "Usable endurance (after reserve)",
      "format": "duration",
      "hint": null,
      "primary": true
    },
    {
      "id": "range",
      "label": "Still-air range at that endurance",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "totalEnduranceHr",
      "label": "Total endurance (no reserve)",
      "format": "duration",
      "hint": null,
      "primary": false
    },
    {
      "id": "groundspeed",
      "label": "Groundspeed used",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "reserveGal",
      "label": "Fuel held for reserve",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Usable fuel: 50 gal",
      "Fuel burn rate: 10 gal/hr",
      "True airspeed: 120 kt",
      "Headwind (negative for tailwind): 10 kt",
      "Required reserve: 45 min"
    ],
    "outputs": [
      "Usable endurance (after reserve): 4.25",
      "Still-air range at that endurance: 468",
      "Total endurance (no reserve): 5",
      "Groundspeed used: 110",
      "Fuel held for reserve: 7.5"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter usable fuel (gal).",
      "Enter fuel burn rate (gal/hr).",
      "Enter true airspeed (kt).",
      "Enter headwind (negative for tailwind) (kt).",
      "Enter required reserve (min).",
      "Read your usable endurance (after reserve) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "usableFuel": 30,
        "burnRate": 6,
        "tas": 70,
        "windComponent": 6,
        "reserveMin": 25
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "usableFuel": 50,
        "burnRate": 10,
        "tas": 120,
        "windComponent": 10,
        "reserveMin": 45
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "usableFuel": 80,
        "burnRate": 16,
        "tas": 190,
        "windComponent": 16,
        "reserveMin": 70
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "Why usable fuel and not total fuel capacity?",
      "a": "Unusable fuel sits below the fuel pickup point in the tank and cannot be drawn under any attitude — it's a certified figure in the POH, typically 1-3 gallons per tank. Using total capacity instead of usable overstates your real endurance by that amount every single flight, which compounds risk on longer legs."
    },
    {
      "q": "How much reserve do I actually need?",
      "a": "14 CFR 91.151 requires 30 minutes reserve for day VFR and 45 minutes for night VFR at normal cruise, while 91.167 requires enough IFR fuel to reach the destination, then the alternate if required, then 45 minutes more. Many pilots plan a full hour reserve regardless of the legal minimum as a personal margin."
    },
    {
      "q": "Does burn rate change with power setting?",
      "a": "Yes, significantly — a burn rate at 75% power can be 20-30% higher than at 55% power for the same airplane. Use the burn rate that matches your actual planned cruise power setting from the POH performance charts, not a generic average, especially for longer cross-countries."
    },
    {
      "q": "What about climb fuel and taxi fuel?",
      "a": "This calculator assumes a single cruise burn rate for simplicity; real flight planning subtracts taxi/runup fuel and climb fuel (which burns more per hour and covers less ground) before applying the cruise burn to the remaining distance. For short trips these deductions matter more proportionally than on long cross-countries."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/aircraft-ownership-cost-per-hour",
    "https://www.revenuelab.fyi/toolbox/climb-performance-fuel",
    "https://www.revenuelab.fyi/toolbox/glide-ratio-distance"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Fuel Endurance & Range Calculator (https://www.revenuelab.fyi/toolbox/fuel-endurance-range)"
}