Of 3,594 sampled departures, 52.8% left 15 minutes or more behind schedule. Average lateness was 32.0 minutes. Sample window: Jan 8, 2026 to May 7, 2026.
These are historical aggregates, not live status. A departure is late at 15 minutes past schedule.
| Airline | Flights sampled | Late | Average lateness |
|---|---|---|---|
| ChallengAir (1I) | 113 | 72.6% | 37.3 min |
| Frontier Airlines, Inc. (F9) | 128 | 59.4% | 48.0 min |
| Southwest Airlines Co. (WN) | 1,851 | 58.9% | 32.7 min |
| United Airlines (UA) | 284 | 58.8% | 43.5 min |
| Alaska Airlines (AS) | 27 | 55.6% | 17.9 min |
52.8% of this STL sample left 15 minutes late or more.
GET /flight_delays returns the ones that are late at this moment: airline, flight number, scheduled time, actual time and minutes of delay.
https://www.goflightlabs.com/flight_delays?access_key=YOUR_ACCESS_KEY&delay=15&type=departures&dep_iata=STLField names match the live API. This flight only shows the shape. It is not a live result.
{
"success": true,
"data": [
{
"airline_iata": "AA",
"flight_iata": "AA100",
"flight_number": "100",
"dep_iata": "STL",
"dep_time": "2024-03-15 08:00",
"dep_actual": "2024-03-15 08:22",
"dep_delayed": 22,
"status": "active"
}
]
}
That URL still says YOUR_ACCESS_KEY.
A 7-day trial replaces it with a real key and returns the STL departures that are late right now, in the JSON above.
After the trial, Starter is $24.99/mo.