---
title: "Observed US air-traffic delay programs - FAA NAS Status"
method: GET
path: "/api/v2/transport/aviation/delays"
tags: ["Transportation"]
---

# Observed US air-traffic delay programs - FAA NAS Status

`GET /api/v2/transport/aviation/delays`

The ground stops, ground delay programs, airport closures, arrival and departure delays and de-icing programs the FAA currently has in force across the United States National Airspace System, each with the FAA's verbatim reason plus a Sugra classification of that free text onto a published vocabulary (weather, runway, volume, equipment, staffing, security). Filter by airport, event type, reason class, delay length and bounding box. This is OBSERVED delay, reported alongside the conditions-based Weather-Disruption-Risk index and never blended into it. United States only; consultative and not a substitute for an official preflight briefing, ATC or your airline.

## Query parameters

- `airports` string, nullable — Comma-separated airport codes. Either the FAA three-letter identifier (JFK) or the four-letter US ICAO form (KJFK), which is normalized to it.
- `type` 'ground_stop' | 'ground_delay' | 'airport_closure' | 'notam' | 'arrival_delay' | 'departure_delay' | 'deicing', nullable — Keep only events of this program type. Asking for `notam` opts into them regardless of `include_notams`.
- `reason_class` 'weather' | 'runway' | 'volume' | 'equipment' | 'staffing' | 'security' | 'other' | 'unknown', nullable — Keep only events matching this Sugra reason class. Matches ANY class the reason carries, not just the dominant one, so a runway closed for snow is found under both `weather` and `runway`.
- `min_delay_minutes` integer, nullable — Keep only events whose upper delay bound reaches this many minutes. Events that publish no delay figure, such as most ground stops, are excluded by it.
- `min_lat` number, nullable — Bounding-box south edge.
- `max_lat` number, nullable — Bounding-box north edge.
- `min_lon` number, nullable — Bounding-box west edge.
- `max_lon` number, nullable — Bounding-box east edge.
- `include_notams` boolean — Include standing airport NOTAMs. Off by default because they are STATUS, not delay: the live feed carries multi-week notices such as an airport closed to transient general aviation except by prior permission, which would otherwise make a perfectly clear airport appear in a delay list. They are still counted in `summary.by_type`, so their existence is never hidden.
- `limit` integer — Maximum airports returned.

## Response `200`

Successful Response

- EnvelopeDelayFeed
  - `data` DelayFeed, required
    - `query` DelayQuery, required
      - `airports` string, nullable
      - `type` string, nullable
      - `reason_class` string, nullable
      - `min_delay_minutes` integer, nullable
      - `include_notams` boolean
      - `min_lat` number, nullable
      - `max_lat` number, nullable
      - `min_lon` number, nullable
      - `max_lon` number, nullable
      - `limit` integer, required
    - `summary` DelaySummary, required
      - `airports_affected` integer, required — Airports in the WHOLE feed, before filters.
      - `events_total` integer, required
      - `by_type` object
      - `by_reason_class` object
    - `total_matched` integer, required
    - `count` integer, required
    - `airports` DelayAirport[] — Ordered by worst_delay_minutes descending, then by airport code. Only airports with an active program appear at all - the feed is not a roster.
      - `airport` string, required — FAA airport code as published by the feed.
      - `name` string, nullable
      - `lat` number, nullable
      - `lon` number, nullable
      - `event_count` integer, required
      - `worst_delay_minutes` integer, nullable — Largest `max_minutes` across this airport's events, or null when no program published a delay figure (a ground stop often does not).
      - `types` string[]
      - `reason_classes` string[]
      - `events` DelayEvent[]
        - `type` string, required — ground_stop | ground_delay | airport_closure | notam | arrival_delay | departure_delay | deicing. `notam` is a standing airport notice rather than an active delay program and is off the default page; see `include_notams`.
        - `reason` string, nullable — The FAA reason, VERBATIM. Free text whose shape varies by program type.
        - `reason_class` string, required — Sugra classification of `reason` onto the published vocabulary. `other` means text that matched no rule; `unknown` means no reason was supplied.
        - `reason_classes` string[] — EVERY class the reason matched, in priority order. A runway closed for snow is genuinely both; `reason_class` is just the first of these.
        - `start_time` string, nullable
        - `end_time` string, nullable
        - `updated_at` string, nullable
        - `min_minutes` integer, nullable — Lower bound of the delay range.
        - `max_minutes` integer, nullable — Upper bound of the delay range.
        - `average_minutes` integer, nullable — The FAA's own average delay figure for this program, where it publishes one. Independent of the min/max range, not derived from it.
        - `trend` string, nullable
        - `center` string, nullable — Issuing air-route traffic control centre.
        - `advisory_url` string, nullable
        - `probability_of_extension` string, nullable
        - `time_raw` string, nullable — Local-time prose carried verbatim from the legacy XML feed. Present only when the fallback feed was used; deliberately NOT parsed, because a mis-read timezone abbreviation would publish a confidently wrong time.
    - `coverage` string, required
    - `classification` object — The published reason vocabulary, priority order and method behind `reason_class`.
    - `attribution` TransportAttributionSet, required
      - `sources` TransportSourceAttribution[] — Every sovereign source that contributed to this response.
        - `registry_key` string, required
        - `source_name` string, required
        - `licence` string, required
        - `citation` string, required
        - `disclaimer` string, required
      - `effective_reexport` string, required — Most-restrictive re-export verdict across the sources.
    - `disclaimer` string, required
    - `upstream` object — Producer diagnostics: which feed was used (`json` primary or `xml` fallback), whether each endpoint answered, and how many records the parser dropped.
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

---

[API](https://skmtc.net/sugra/apis/sugra-api.md) · [All operations](https://skmtc.net/sugra/apis/sugra-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/sugra/sugra-api/revisions/4e2740743eb4/schema)