# Aviation Calculators – Fuel, Time & Distance (E6B)

> Aviation Calculators – Fuel, Time & Distance (E6B) is a paid API for AI agents from aviation-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Solves E6B flight computer arithmetic for any two of distance, groundspeed, and time, plus fuel burn, reserve fuel, and range calculations.

## Facts

- Endpoint: GET https://aviation-calc.x402tookit.com/fuel-time-distance?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aviation-calculators-fuel-time-distance-e6b-50a0339e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HbdVs9uwVzJtw1NIIQ0km

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability aviation-calculators-fuel-time-distance-e6b-50a0339e
```

Example prompt: I'm planning a 185 nm leg at 125 knots groundspeed with a fuel flow of 8.5 gallons per hour and 40 gallons usable on board — can you work out my flight time, trip fuel, reserve fuel (use a 45-minute reserve), and how much range I have to reserve?

## When to prefer this

Use this endpoint when you need quick E6B-style arithmetic for a single flight leg — especially when checking fuel reserves, computing flight time, or back-solving groundspeed. It is purpose-built for aviation calculations with correct unit handling (knots, nautical miles, minutes) and built-in VFR/IFR reserve logic, making it preferable to a generic calculator for any pilot-facing agent or flight-planning workflow.

## Known failure modes

- Missing required combination of inputs — at least two of distance, groundspeed, or time must be provided for the triangle solve
- Out-of-range reserveMin value (must be 0–240 minutes)
- Negative or zero values for speed, distance, or fuel causing nonsensical results
- Insufficient inputs to compute fuel outputs if fuelFlowPerHour or fuelOnBoard are omitted
- HTTP 402 if the x402 payment header is missing or the USDC balance is insufficient

## How this service works

E6B arithmetic: give any two of distance, groundspeed and time for the third, plus fuel burn, reserve and range.

## Output

Returns a JSON object with the computed unknowns filled in (timeMin, timeHhMm, distanceNm, groundspeedKt), plus tripFuel, reserveFuel, enduranceHours, enduranceHhMm, enduranceToReserveHhMm, rangeNmToReserve, maxRangeNmNoReserve, a human-readable summary, a verdict (e.g. pass/fail on fuel check), a list of reasons, and a disclaimer. Fields not computable from the inputs provided are returned as null.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {
      "timeMin": {
       "type": "number",
       "description": "Time in minutes"
      },
      "distanceNm": {
       "type": "number",
       "description": "Distance in nautical miles"
      },
      "reserveMin": {
       "type": "number",
       "description": "Reserve in minutes, 0 to 240 (default 45; US VFR rules are 30 minutes day, 45 night, and IFR needs 45 beyond the alternate)"
      },
      "fuelOnBoard": {
       "type": "number",
       "description": "Usable fuel on board in the same unit, to check the reserve and range"
      },
      "groundspeedKt": {
       "type": "number",
       "description": "Groundspeed in knots"
      },
      "fuelFlowPerHour": {
       "type": "number",
       "description": "Fuel burn per hour in your unit (gallons, litres, pounds)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "timeMin": {
       "type": [
        "null",
        "number"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "timeHhMm": {
       "type": [
        "null",
        "string"
       ]
      },
      "tripFuel": {
       "type": [
        "null",
        "number"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "distanceNm": {
       "type": [
        "null",
        "nu
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/aviation-calculators-fuel-time-distance-e6b-50a0339e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from aviation-calc.x402tookit.com](https://www.zero.xyz/host/aviation-calc.x402tookit.com/llms.txt)