Apparatus

Try JFK, AAL1290, BAW, or N225AN.

flight_takeoff Flight

UAL3900

Operated by United Airlines

Live map

Live map filtered to UAL3900. Shown when the flight is currently airborne.

Route airports View route page →

Departure

SJC KSJC VFR

Norman Y. Mineta San Jose International Airport

San Jose, US

Local time
06:42 PDT
Timezone
America/Los_Angeles
Type
Large Airport
Elevation
62 ft
Coordinates
37.3625, -121.9292

cloud Weather

Wind
140° / 3 kt
Visibility
10 SM
Ceiling
FEW 7,500 ft, FEW 9,500 ft
Temp / Dew
11°C / 6°C
Altimeter
29.85 inHg

Obs: 2026-10-12T12:53:00.000Z

Raw METAR / TAF 
METAR KSJC 121253Z 14003KT 10SM FEW075 FEW095 11/06 A2985 RMK AO2 SLP106 T01060061

TAF KSJC 121120Z 1212/1312 VRB05KT P6SM FEW080 FEW100 FM122000 32008KT P6SM SKC

flight Live Traffic

flight_takeoff 28 Departures
flight_land 31 Arrivals

Arrival

DEN KDEN VFR

Denver International Airport

Denver, US

Local time
07:42 MDT
Timezone
America/Denver
Type
Large Airport
Elevation
5,431 ft
Coordinates
39.8600, -104.6738

cloud Weather

Wind
190° / 12 kt
Visibility
10 SM
Ceiling
FEW 8,000 ft, FEW 20,000 ft
Temp / Dew
15°C / 2°C
Altimeter
29.83 inHg

Obs: 2026-10-12T12:53:00.000Z

Raw METAR / TAF 
METAR KDEN 121253Z 19012KT 10SM FEW080 FEW200 15/02 A2983 RMK AO2 SLP032 T01500017

TAF KDEN 121136Z 1212/1318 20015KT P6SM SKC FM121600 23014G21KT P6SM SKC FM130100 18009KT P6SM SKC FM130500 35010KT P6SM FEW020 SCT040 FM131000 02008KT P6SM BKN020 FM131600 05007KT P6SM FEW020 BKN040

flight Live Traffic

flight_takeoff 217 Departures
flight_land 369 Arrivals

Recent history last 30

DateAircraftRouteTakeoffLandingDurationDep ΔArr Δ
2026-07-25 A28DC8 SJC → DEN Jul 25, 19:45 UTCJul 26, 00:55 UTC5h 10m - -
2026-07-25 A28DC8 SJC → DEN Jul 25, 19:44 UTCJul 26, 00:50 UTC5h 6m +104m +2m
2026-07-20 A449A4 - Jul 20, 07:00 UTCJul 20, 08:30 UTC1h 30m - -
2026-07-19 A612A6 - Jul 19, 15:50 UTCJul 19, 19:15 UTC3h 25m - -
2026-07-15 A0A8DE EWR → ORD Jul 15, 05:20 UTCJul 15, 07:05 UTC1h 45m - -
2026-07-11 A12F2A - Jul 11, 11:25 UTCJul 11, 12:10 UTC45m - -
2026-07-06 A44611 - Jul 6, 20:50 UTCJul 6, 22:45 UTC1h 55m - -
2026-07-04 A46D26 - Jul 4, 00:10 UTCJul 4, 01:55 UTC1h 45m - -
2026-07-02 AC0AAC SJC → DEN Jul 2, 13:00 UTCJul 2, 13:30 UTC30m - -
2026-06-29 A1D8FD SJC → DEN Jun 29, 22:39 UTCJun 30, 01:14 UTC2h 35m - -
2026-06-29 A1D8FD SJC → DEN Jun 29, 22:17 UTCJun 30, 01:38 UTC3h 21m +17m -17m
2026-06-28 AB050F SJC → DEN Jun 28, 09:55 UTCJun 28, 11:35 UTC1h 40m - -
2026-06-22 A5CC12 SJC → DEN Jun 22, 03:10 UTCJun 22, 03:54 UTC45m - -
2026-06-19 AAA125 SJC → DEN Jun 19, 22:56 UTCJun 20, 01:36 UTC2h 40m +26m +5m
2026-06-19 AAA125 SJC → DEN Jun 19, 22:49 UTCJun 20, 01:39 UTC2h 50m - -
2026-06-14 A12733 SJC → DEN Jun 14, 07:05 UTCJun 14, 07:45 UTC40m - -
2026-06-12 A6045D SJC → DEN Jun 12, 11:40 UTCJun 12, 12:45 UTC1h 5m - -
2026-06-12 A6045D SJC → DEN Jun 12, 11:29 UTCJun 12, 12:34 UTC1h 5m +29m -21m
2026-06-12 A126C3 SJC → DEN Jun 12, 06:30 UTCJun 12, 07:10 UTC40m - -
2026-06-10 A0ACFD SJC → DEN Jun 10, 18:45 UTCJun 10, 19:50 UTC1h 5m - -
2026-06-06 A43EC9 SJC → DEN Jun 6, 15:30 UTCJun 6, 17:05 UTC1h 35m - -
2026-06-01 A9067B SJC → DEN Jun 1, 09:15 UTCJun 1, 18:10 UTC8h 55m - -
2026-06-01 A9067B SJC → DEN Jun 1, 08:50 UTCJun 1, 18:15 UTC9h 25m +890m +34m
2026-05-26 A12F6F SJC → DEN May 26, 03:55 UTCMay 26, 04:50 UTC55m - -
2026-05-16 A1B5E7 SJC → DEN May 16, 00:40 UTCMay 16, 00:55 UTC15m - -
2026-05-15 A1B5E7 SJC → DEN May 15, 15:15 UTCMay 16, 00:55 UTC9h 40m - -
2026-05-15 A1B5E7 SJC → DEN May 15, 14:20 UTCMay 15, 14:30 UTC10m - -
2026-05-15 A1B5E7 SJC → DEN May 15, 13:45 UTCMay 16, 00:23 UTC10h 38m +15m +9m
2026-05-08 A89D59 SJC → DEN May 8, 14:25 UTCMay 8, 15:05 UTC40m - -
2026-05-05 AA6B9F SJC → DEN May 5, 16:50 UTCMay 5, 20:01 UTC3h 10m - -

Performance history

Flights tracked
33 showing last 30
Avg arrival delay
+2m
On-time arrival
83% 83% on time
Aircraft used
22

Monthly activity 4 months

Month Flights tracked
July 2026 9
June 2026 14
May 2026 9
April 2026 1

UAL3900 frequently asked

Where does flight UAL3900 fly?
UAL3900 (United Airlines) flies from SJC to DEN. View the full route page.
How long is flight UAL3900?
Based on observed flights, UAL3900 takes on average 2h 51m from takeoff to landing.
How often does UAL3900 fly?
UAL3900 has been observed flying several times a week in our tracking data. We've recorded 33 flights under this callsign.
Is flight UAL3900 usually on time?
Across recent flights, UAL3900 arrives with an average 2-minute delay. 83% of flights arrive within 15 minutes of schedule.
What aircraft operates flight UAL3900?
UAL3900 has been operated by 22 different aircraft in our records. Tail numbers are listed in the recent history below.
Can I track UAL3900 live?
Yes. When UAL3900 is currently airborne, the live tracker map above shows its real-time position from ADS-B broadcasts. If the map is empty, the flight is not currently in the air.