About 1 in 7 DL 4939 flights from New York arrived 15+ minutes late, diverted or cancelled over the past year (15%); 3.3% were cancelled. The typical flight landed 13 minutes early.
DL 4939: LGA → STL
Scheduled to leave New York at 6:30 a.m. local time, operated by Endeavor Air as 9E 4939. Over the past year it arrived on time 85% of the time (272 flights), in line with other DL flights on the route at that hour (84%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 50 | 76% |
| Tuesday | 49 | 82% |
| Wednesday | 49 | 88% |
| Thursday | 48 | 92% |
| Friday | 48 | 83% |
| Sunday | 28 | 93% |
Why it was late
All flights LGA → STL · Connecting off DL 4939? Check the risk
Questions
How often is DL 4939 from LGA to STL late?
Delta Air Lines 4939 from New York, NY to St. Louis, MO arrived 15 or more minutes late, was diverted or was cancelled on 15% of 272 scheduled flights between September 2025 and August 2026. 3.3% were cancelled.
Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.