United Airlines
Is UA3939 delayed?
Service date: · Scheduled departure date (America/Los_Angeles)
Arrived
23 min late
Official source · Updated
Departure
San Francisco
SFO
Actual
Scheduled 22:23
Sep 14
Arrival
Denver
DEN
Actual
Scheduled 01:40
Sep 15
Times shown in airport local time
Flight details
Departure · UTC
- Scheduled
- Estimated
- Not available
- Actual
Arrival · UTC
- Scheduled
- Estimated
- Not available
- Actual
Recent arrivals
Dates below are arrival dates in the destination airport’s time zone. The detailed history uses service dates.
- 23 min late
SFO → DEN
- 36 min late
CDG → IAD
- 127 min late
DEN → SFO
Flight history and details
Aug 17, 2026 — Sep 16, 2026
- Observed arrivals
- 3
- Arrivals over 15 minutes late
- 3
- Observed cancellations
- 1
- Observed occurrences
- 4
Results compare scheduled and actual arrival times. Cancelled or diverted flights are excluded. Some flights may be missing from the history.
| Service date | Departure | Arrival | Actual | Arrival delay (minutes) |
|---|---|---|---|---|
| Sep 14, 2026Arrived | San Francisco | Denver | 23 | |
| Sep 10, 2026Arrived | Paris | Dulles | 36 | |
| Sep 8, 2026Arrived | Denver | San Francisco | 127 | |
| Sep 6, 2026Cancelled | Los Angeles | Dulles | Not available | Not available |