About 1 in 5 DL 4001 flights from Los Angeles arrived 15+ minutes late, diverted or cancelled over the past year (21%); 0.4% were cancelled. The typical flight landed 2 minutes early.
DL 4001: LAX → SAN
Scheduled to leave Los Angeles at 2:11 p.m. local time, operated by SkyWest as OO 4001. Over the past year it arrived on time 79% of the time (289 flights), in line with other DL flights on the route at that hour (77%). Last seen in the data Aug 31, 2026.
Month by month
By day of week
| Day | Flights | On time |
|---|---|---|
| Monday | 45 | 67% |
| Tuesday | 44 | 95% |
| Wednesday | 44 | 91% |
| Thursday | 43 | 74% |
| Friday | 42 | 71% |
| Saturday | 28 | 86% |
| Sunday | 43 | 70% |
Why it was late
All flights LAX → SAN · Connecting off DL 4001? Check the risk
Questions
How often is DL 4001 from LAX to SAN late?
Delta Air Lines 4001 from Los Angeles, CA to San Diego, CA arrived 15 or more minutes late, was diverted or was cancelled on 21% of 289 scheduled flights between September 2025 and August 2026. 0.4% 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.