> ## Documentation Index > Fetch the complete documentation index at: https://docs.flightportrait.com/llms.txt > Use this file to discover all available pages before exploring further. # Estimated positions > Aircraft the network stopped hearing while cruising, drawn where they most likely are: flown on from the last observed position toward the destination their callsign's route names, at the last observed speed (holding the last track 10 minutes, then turning toward the destination). Every entry is an estimate, never an observation: `estimated` is always true, `last_seen` is the last real position, `alt_baro` and `gs` are the last observed values. An aircraft appears 90 s after it was last heard and leaves when it is heard again, nears its destination, or its flight time runs out. Kept in memory, never archived or exported. Scored every night against the previous day's real coverage gaps; `accuracy` is the latest night's result for the method in use (median error by gap length), null before the first. Rate: 300 per 600 s (bucket `estimated`). Cache: 15 s edge, 10 s browser. ## OpenAPI ````yaml /openapi.json get /v1/estimated openapi: 3.1.0 info: title: FlightPortrait network API description: >- Open data from the FlightPortrait receiver network. No API key. **Stability.** Operations marked `x-stability: stable` only ever gain fields; names and types are frozen. Operations marked `x-stability: map` exist for the first-party map and can change with it. **Field dialects.** `/v1/aircraft` and `/v2/point` pass readsb's wire fields through unchanged (`hex`, `t`, `r`, `gs`, ...) so ecosystem tooling works as-is. Every other resource uses full words: `reg`, `type`, `org`, `dst`. Airport codes in history resources are IATA; `/v1/airports/{code}` accepts IATA or ICAO. Event times are unix seconds UTC; registry timestamps are ISO 8601 UTC; board and schedule times are HH:MM in the origin airport's local time. **Data honesty.** History is observation, never an official registry. Gaps mean the network's sources did not hear it, nothing more. Responses carry `coverage: "observed"` as a reminder. The one exception is the airport departures board, whose rows may be inferred from published timetables — each board row carries its own `source` (observed / published / both); a published row is not a receiver observation. Likewise a flight's `route_source`: `observed` when both ends were seen, `observed+catalog` when the community supplied the end coverage never reached, `catalog` when it supplied both. Catalog answers are checked against observation and reviewed before they are served, and observation outranks them whenever it speaks. This API is read-only; answers go to the contribution door at contribute.flightportrait.com. **Errors.** Every non-200 body is `{"error": , "detail": }` with `Cache-Control: no-store`. 404 `not_found` / `not_observed`, 422 `invalid_request`, 429 `rate_limited` (with `Retry-After` and `RateLimit-*` headers), 503 `stale_snapshot` (live snapshot older than 60 s) or `artifact_unavailable` (a history artifact is not loaded). **Rate limits.** Per IP, per bucket, over a 600 second window; each operation notes its bucket and default limit. 429 means wait for `Retry-After` seconds. Data is ODbL 1.0. Credit "FlightPortrait network feeders" and link the credits page, which lists every source the data draws on and the credit each one asks for; republishing carries them too. Credits: https://flightportrait.com/network/credits.html Terms: https://flightportrait.com/network/terms version: 1.0.0 servers: - url: https://data.flightportrait.com security: [] tags: - name: Live description: What the network hears now. - name: History description: Observed airframes, flights, airports. - name: Stations description: Feeder roster. - name: Reference description: Airlines, alliances, types. - name: Contributions description: What observation could not settle, and the community answers to it. - name: Meta description: Index and health. paths: /v1/estimated: get: tags: - Live summary: Estimated positions description: >- Aircraft the network stopped hearing while cruising, drawn where they most likely are: flown on from the last observed position toward the destination their callsign's route names, at the last observed speed (holding the last track 10 minutes, then turning toward the destination). Every entry is an estimate, never an observation: `estimated` is always true, `last_seen` is the last real position, `alt_baro` and `gs` are the last observed values. An aircraft appears 90 s after it was last heard and leaves when it is heard again, nears its destination, or its flight time runs out. Kept in memory, never archived or exported. Scored every night against the previous day's real coverage gaps; `accuracy` is the latest night's result for the method in use (median error by gap length), null before the first. Rate: 300 per 600 s (bucket `estimated`). Cache: 15 s edge, 10 s browser. operationId: estimated responses: '200': description: OK content: application/json: schema: properties: generated_at: type: number description: Unix seconds the estimates are for. method: type: string description: How positions are estimated. accuracy: type: - object - 'null' description: >- The latest night's measured accuracy: day, n, median_km, by_gap_min. aircraft: items: type: object type: array description: >- Estimated aircraft; every entry is an estimate, never an observation. type: object required: - generated_at - method - aircraft example: generated_at: 1790140000 method: converge-to-destination accuracy: day: '2026-09-22' 'n': 208 median_km: 2.3 by_gap_min: 5-15: 'n': 153 median_km: 1.4 60-120: 'n': 43 median_km: 76.9 aircraft: - hex: 4ca8e4 flight: RYR1153 t: B738 r: 9H-QDS category: A3 lat: 43.1021 lon: 11.9403 track: 312.4 alt_baro: 36000 gs: 452 estimated: true last_seen: at: 1790139412 lat: 42.2 lon: 13.1 destination: PSA eta: 1790140700 '429': description: >- Rate limited. Wait Retry-After seconds. Headers: Retry-After, RateLimit-Limit, RateLimit-Remaining, RateLimit-Reset. content: application/json: schema: properties: error: type: string description: >- Machine code: not_found, not_observed, invalid_request, rate_limited, stale_snapshot, artifact_unavailable, upstream_unavailable. detail: type: string description: Human-readable explanation. type: object required: - error - detail example: error: rate_limited detail: slow down ````