{
  "slug": "aircraft-weight-balance",
  "title": "Aircraft Weight & Balance Calculator",
  "heading": "Aircraft Weight & Balance Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/aircraft-weight-balance",
  "summary": "Gross weight and center of gravity for a light aircraft.",
  "description": "Sum station weights and moments to get gross weight and CG arm. Educational estimate — always fly the numbers in your POH.",
  "formula": "CG = Σ(weight × arm) ÷ Σ(weight).",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=aircraft-weight-balance",
  "inputs": [
    {
      "id": "empty",
      "label": "Empty weight",
      "kind": "number",
      "hint": null,
      "default": 1500,
      "unit": "lb",
      "min": null,
      "max": null
    },
    {
      "id": "emptyArm",
      "label": "Empty CG arm",
      "kind": "number",
      "hint": null,
      "default": 39,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "front",
      "label": "Front seats",
      "kind": "number",
      "hint": null,
      "default": 340,
      "unit": "lb",
      "min": null,
      "max": null
    },
    {
      "id": "frontArm",
      "label": "Front seat arm",
      "kind": "number",
      "hint": null,
      "default": 37,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "rear",
      "label": "Rear seats",
      "kind": "number",
      "hint": null,
      "default": 160,
      "unit": "lb",
      "min": null,
      "max": null
    },
    {
      "id": "rearArm",
      "label": "Rear seat arm",
      "kind": "number",
      "hint": null,
      "default": 73,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "fuel",
      "label": "Fuel",
      "kind": "number",
      "hint": null,
      "default": 40,
      "unit": "gal",
      "min": null,
      "max": null
    },
    {
      "id": "fuelArm",
      "label": "Fuel arm",
      "kind": "number",
      "hint": null,
      "default": 48,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "bag",
      "label": "Baggage",
      "kind": "number",
      "hint": null,
      "default": 50,
      "unit": "lb",
      "min": null,
      "max": null
    },
    {
      "id": "bagArm",
      "label": "Baggage arm",
      "kind": "number",
      "hint": null,
      "default": 95,
      "unit": "in",
      "min": null,
      "max": null
    },
    {
      "id": "maxGross",
      "label": "Max gross weight",
      "kind": "number",
      "hint": null,
      "default": 2450,
      "unit": "lb",
      "min": null,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "gross",
      "label": "Gross weight (lb)",
      "format": "number",
      "hint": null,
      "primary": true
    },
    {
      "id": "cg",
      "label": "CG arm (in)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "status",
      "label": "Gross weight check",
      "format": "raw",
      "hint": null,
      "primary": false
    },
    {
      "id": "moment",
      "label": "Total moment (lb-in)",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Empty weight: 1500 lb",
      "Empty CG arm: 39 in",
      "Front seats: 340 lb",
      "Front seat arm: 37 in",
      "Rear seats: 160 lb",
      "Rear seat arm: 73 in",
      "Fuel: 40 gal",
      "Fuel arm: 48 in",
      "Baggage: 50 lb",
      "Baggage arm: 95 in",
      "Max gross weight: 2450 lb"
    ],
    "outputs": [
      "Gross weight (lb): 2,290",
      "CG arm (in): 43.24",
      "Gross weight check: Under gross by 160 lb",
      "Total moment (lb-in): 99,030"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter empty weight (lb).",
      "Enter empty cg arm (in).",
      "Enter front seats (lb).",
      "Enter front seat arm (in).",
      "Enter rear seats (lb).",
      "Enter rear seat arm (in).",
      "Enter fuel (gal).",
      "Enter fuel arm (in).",
      "Enter baggage (lb).",
      "Enter baggage arm (in).",
      "Enter max gross weight (lb).",
      "Read your gross weight (lb) 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": {
        "empty": 900,
        "emptyArm": 23.4,
        "front": 200,
        "frontArm": 22.2,
        "rear": 100,
        "rearArm": 43.8,
        "fuel": 24,
        "fuelArm": 28.799999999999997,
        "bag": 30,
        "bagArm": 57,
        "maxGross": 1470
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "empty": 1500,
        "emptyArm": 39,
        "front": 340,
        "frontArm": 37,
        "rear": 160,
        "rearArm": 73,
        "fuel": 40,
        "fuelArm": 48,
        "bag": 50,
        "bagArm": 95,
        "maxGross": 2450
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "empty": 2400,
        "emptyArm": 62.400000000000006,
        "front": 540,
        "frontArm": 59.2,
        "rear": 260,
        "rearArm": 116.80000000000001,
        "fuel": 64,
        "fuelArm": 76.80000000000001,
        "bag": 80,
        "bagArm": 152,
        "maxGross": 3920
      }
    }
  ],
  "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": "How does the aircraft weight & balance calculator work?",
      "a": "Sum station weights and moments to get gross weight and CG arm. Educational estimate — always fly the numbers in your POH. The underlying maths is: CG = Σ(weight × arm) ÷ Σ(weight)."
    },
    {
      "q": "What do I need to enter?",
      "a": "11 values: empty weight, empty cg arm, front seats, front seat arm, rear seats, rear seat arm, fuel, fuel arm, baggage, baggage arm, and max gross weight. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the gross weight (lb) result mean?",
      "a": "It is returned as a whole number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/aircraft-fuel-burn",
    "https://www.revenuelab.fyi/toolbox/density-altitude"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Aircraft Weight & Balance Calculator (https://www.revenuelab.fyi/toolbox/aircraft-weight-balance)"
}