Apparatus

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flight_takeoff Flight

UAL3940

Operated by United Airlines

Live map

Live map filtered to UAL3940. Shown when the flight is currently airborne.

Route airports View route page →

Departure

DEN KDEN VFR

Denver International Airport

Denver, US

Local time
19:06 MDT
Timezone
America/Denver
Type
Large Airport
Elevation
5,431 ft
Coordinates
39.8600, -104.6738

cloud Weather

Wind
290° / 7 kt
Visibility
10 SM
Ceiling
FEW 7,000 ft, SCT 11,000 ft, BKN 20,000 ft
Temp / Dew
23°C / 6°C
Altimeter
29.79 inHg

Obs: 2026-05-30T00:53:00.000Z

Raw METAR / TAF 
METAR KDEN 300053Z 29007KT 10SM FEW070 SCT110 BKN200 23/06 A2979 RMK AO2 SLP018 T02280056

TAF KDEN 300002Z 3000/3106 32010KT P6SM VCSH SCT070 BKN110 BKN150 FM300200 03010KT P6SM SCT100 BKN150 FM300600 32007KT P6SM FEW100 SCT200 FM300900 25006KT P6SM FEW100 SCT200 FM301400 28009KT P6SM SCT180 FM302100 31012KT P6SM VCSH SCT100 PROB30 3021/3101 VRB15G25KT FM310300 27013KT P6SM FEW080 SCT100

warning FAA Advisories

  • Ground Delay: thunderstorms (avg 59 minutes)

flight Live Traffic

flight_takeoff 447 Departures
flight_land 540 Arrivals

Arrival

SEA KSEA VFR

Seattle–Tacoma International Airport

Seattle, US

Local time
18:06 PDT
Timezone
America/Los_Angeles
Type
Large Airport
Elevation
433 ft
Coordinates
47.4479, -122.3103

cloud Weather

Wind
30° / 10 kt
Visibility
10 SM
Ceiling
FEW 5,000 ft, BKN 7,000 ft
Temp / Dew
14°C / 8°C
Altimeter
30.08 inHg

Obs: 2026-05-30T00:53:00.000Z

Raw METAR / TAF 
METAR KSEA 300053Z 03010KT 10SM FEW050 BKN070 14/08 A3008 RMK AO2 SLP192 T01440083 $

TAF KSEA 292339Z 3000/3106 03005KT P6SM FEW020 BKN035 FM300300 03010KT P6SM BKN050 FM301200 10005KT P6SM BKN030 FM301900 28006KT P6SM BKN070

flight Live Traffic

flight_takeoff 240 Departures
flight_land 285 Arrivals

Recent history last 17

DateAircraftRouteTakeoffLandingDurationDep ΔArr Δ
2026-05-28 A913D6 DEN → SEA May 28, 12:40 UTCMay 28, 14:19 UTC1h 39m +100m +11m
2026-05-28 A913D6 DEN → SEA May 28, 12:40 UTCMay 28, 14:35 UTC1h 55m - -
2026-05-21 A87223 DEN → SEA May 21, 16:29 UTCMay 21, 19:39 UTC3h 10m +929m -20m
2026-05-21 A87223 DEN → SEA May 21, 16:35 UTCMay 21, 19:45 UTC3h 10m - -
2026-05-19 A5CF41 DEN → SEA May 19, 13:55 UTCMay 19, 14:15 UTC20m - -
2026-05-19 A5CF41 DEN → SEA May 19, 14:03 UTCMay 19, 14:09 UTC6m +18m +5m
2026-05-17 ABB7F7 DEN → SEA May 17, 01:30 UTCMay 17, 01:45 UTC15m - -
2026-05-17 ABB7F7 DEN → SEA May 17, 01:07 UTCMay 17, 02:08 UTC1h 1m +17m -26m
2026-05-10 A12F73 DEN → SEA May 10, 16:44 UTCMay 10, 18:20 UTC1h 35m - -
2026-05-10 A12F73 DEN → SEA May 10, 16:31 UTCMay 10, 18:11 UTC1h 40m +91m -12m
2026-05-05 A43EEC DEN → SEA May 5, 05:05 UTCMay 5, 10:35 UTC5h 30m - -
2026-05-03 A2C336 DEN → SEA May 3, 13:15 UTCMay 3, 14:00 UTC45m - -
2026-04-30 A2CA5F DEN → SEA Apr 30, 23:45 UTCMay 1, 01:05 UTC1h 20m - -
2026-04-28 A0BF8C DEN → SEA Apr 28, 14:10 UTCApr 28, 15:05 UTC55m - -
2026-04-25 AC59AA DEN → SEA Apr 25, 23:30 UTCApr 26, 00:15 UTC45m - -
2026-04-22 AA7F03 DEN → SEA Apr 22, 12:05 UTCApr 22, 16:25 UTC4h 20m - -
2026-04-14 A44984 - Apr 14, 12:55 UTCApr 14, 13:40 UTC45m - -

Performance history

Flights tracked
17
Avg arrival delay
-8m
On-time arrival
100% 100% on time
Aircraft used
12

Monthly activity 2 months

Month Flights tracked
May 2026 12
April 2026 5

UAL3940 frequently asked

Where does flight UAL3940 fly?
UAL3940 (United Airlines) flies from DEN to SEA. View the full route page.
How long is flight UAL3940?
Based on observed flights, UAL3940 takes on average 1h 43m from takeoff to landing.
How often does UAL3940 fly?
UAL3940 has been observed flying several times a week in our tracking data. We've recorded 17 flights under this callsign.
Is flight UAL3940 usually on time?
Across recent flights, UAL3940 arrives 8 minutes early on average. 100% of flights arrive within 15 minutes of schedule.
What aircraft operates flight UAL3940?
UAL3940 has been operated by 12 different aircraft in our records. Tail numbers are listed in the recent history below.
Can I track UAL3940 live?
Yes. When UAL3940 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.