Of 1,094 sampled 9K departures, 45.0% left 15 minutes or more behind schedule. Average lateness was 35.8 minutes. Sample window: Nov 4, 2025 to Oct 31, 2026.
These are historical aggregates, not live status. A departure is late at 15 minutes past schedule.
| Month | Departures sampled | Late | Average lateness |
|---|---|---|---|
| Nov 2025 | 74 | 50.0% | 29.2 min |
| Dec 2025 | 76 | 57.9% | 44.8 min |
| Jan 2026 | 145 | 46.9% | 44.2 min |
| Mar 2026 | 385 | 35.8% | 33.8 min |
| May 2026 | 141 | 41.1% | 47.4 min |
| Jun 2026 | 64 | 59.4% | 27.1 min |
| Jul 2026 | 76 | 51.3% | 24.3 min |
| Aug 2026 | 34 | 58.8% | 24.5 min |
| Sep 2026 | 32 | 46.9% | 24.1 min |
| Oct 2026 | 64 | 51.6% | 34.8 min |
| Departure airport | Departures sampled | Late | Average lateness |
|---|---|---|---|
| Boston Logan International Airport (BOS) | 573 | 42.2% | 40.0 min |
| John F. Kennedy International Airport (JFK) | 360 | 55.6% | 36.3 min |
| Billings Logan International Airport (BIL) | 131 | 32.8% | 19.6 min |
GET /flight_delays filtered by airline_iata=9K returns the flights delayed at this moment: flight number, scheduled and actual times and minutes of delay.
That URL still says YOUR_ACCESS_KEY.
A 7-day trial replaces it with a real key. After the trial, Starter is $24.99/mo.
