Specific range API

Computes specific range (distance per fuel unit) in still air and over the ground from TAS, fuel flow and an optional headwind. Answers 'How many nm per gallon do I get over the ground?', 'How much fuel do I burn per nautical mile into a headwind?'.

Price$0.04per request

MethodPOST

Route/v1/nav/specific-range

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

aviationspecific-rangefuel-efficiencyfuel-flowtasheadwindeconomycruise

API URLhttps://x402.hexl.dev/v1/nav/specific-range

Integration docs

Example request

{
  "trueAirspeedKt": 450,
  "fuelFlowPerHour": 2500,
  "headwindKt": 50
}

Example response

{
  "groundSpeedKt": 400,
  "specificRangeStillAirNmPerUnit": 0.18,
  "specificRangeOverGroundNmPerUnit": 0.16,
  "fuelPerNmUnits": 6.25,
  "interpretation": "0.16 nm per fuel unit over the ground (0.18 still-air); 6.25 units burned per nm."
}

Input schema

{
  "type": "object",
  "required": [
    "trueAirspeedKt",
    "fuelFlowPerHour"
  ],
  "properties": {
    "trueAirspeedKt": {
      "type": "number",
      "examples": [
        450
      ]
    },
    "fuelFlowPerHour": {
      "type": "number",
      "examples": [
        2500
      ]
    },
    "headwindKt": {
      "type": "number",
      "examples": [
        50
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}