Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A44940

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N37538 · BOEING 737 MAX 9 · operated by UNITED AIRLINES INC

Hex
A44940
Octal
51044500
Decimal
10,766,656
Country
US
Tail
N37538
Type
B39M
Broadcasting now · callsign UAL1250 · 15,925 ft
Flights observed
474
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 22:00 UTC

Current position

A44940 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A44940 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 20 distinct

Callsign Airline Flights Last seen
UAL650 United Airlines 5 2026-06-05
UAL2380 United Airlines 5 2026-06-04
UAL701 United Airlines 4 2026-07-25
UAL2491 United Airlines 4 2026-05-21
UAL2404 - 4 2026-07-13
UAL1618 - 4 2026-06-24
UAL1372 United Airlines 4 2026-04-27
UAL1123 - 4 2026-06-29
UAL731 United Airlines 3 2026-07-21
UAL668 - 3 2026-07-05
UAL665 United Airlines 3 2026-05-28
UAL620 - 3 2026-07-15
UAL2746 United Airlines 3 2026-06-23
UAL2667 United Airlines 3 2026-05-14
UAL2495 United Airlines 3 2026-07-25
UAL2363 United Airlines 3 2026-06-10
UAL2274 United Airlines 3 2026-06-07
UAL215 United Airlines 3 2026-06-21
UAL2125 United Airlines 3 2026-05-24
UAL2029 United Airlines 3 2026-06-10

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL2086 EWR → ATL Jul 26, 19:10 UTCJul 26, 22:00 UTC2h 50m
2026-07-26 UAL203 SFO → ABQ Jul 26, 16:40 UTCJul 26, 17:20 UTC40m
2026-07-26 UAL751 EWR → SFO Jul 26, 01:05 UTCJul 26, 02:15 UTC1h 10m
2026-07-25 UAL2279 EWR → MSY Jul 25, 21:10 UTCJul 25, 22:40 UTC1h 30m
2026-07-25 UAL1301 CLT → ORD Jul 25, 18:45 UTCJul 25, 20:00 UTC1h 15m
2026-07-25 UAL2744 MCO → EWR Jul 25, 13:50 UTCJul 25, 17:10 UTC3h 20m
2026-07-25 UAL2495 SRQ → EWR Jul 25, 07:00 UTCJul 25, 10:30 UTC3h 30m
2026-07-25 UAL2495 SRQ → EWR Jul 25, 06:20 UTCJul 25, 06:30 UTC10m
2026-07-25 UAL2495 SRQ → EWR Jul 25, 06:17 UTCJul 25, 10:28 UTC4h 11m
2026-07-25 UAL701 MSY → EWR Jul 25, 00:15 UTCJul 25, 00:35 UTC20m
2026-07-24 UAL701 MSY → EWR Jul 24, 20:25 UTCJul 24, 22:40 UTC2h 15m
2026-07-24 UAL462 EWR → PBI Jul 24, 14:30 UTCJul 24, 18:15 UTC3h 45m
2026-07-23 UAL1964 IAD → SEA Jul 23, 22:05 UTCJul 24, 01:55 UTC3h 50m
2026-07-23 UAL1795 DEN → CLE Jul 23, 17:10 UTCJul 23, 19:20 UTC2h 10m
2026-07-23 UAL2469 - Jul 23, 13:15 UTCJul 23, 15:40 UTC2h 25m
2026-07-23 UAL780 IAD → LAS Jul 23, 07:35 UTCJul 23, 11:15 UTC3h 40m
2026-07-23 UAL1420 MCO → EWR Jul 23, 02:45 UTCJul 23, 06:20 UTC3h 35m
2026-07-22 UAL1058 CUN → IAH Jul 22, 22:55 UTCJul 23, 01:05 UTC2h 10m
2026-07-22 UAL1679 SFO → CUN Jul 22, 16:20 UTCJul 22, 19:50 UTC3h 30m
2026-07-22 UAL1679 SFO → CUN Jul 22, 16:08 UTCJul 22, 21:08 UTC5h 0m
2026-07-22 UAL1724 KOA → SFO Jul 22, 12:35 UTCJul 22, 13:15 UTC40m
2026-07-22 UAL1723 SBA → SFO Jul 22, 00:30 UTCJul 22, 00:55 UTC25m
2026-07-22 UAL1723 SBA → SFO Jul 22, 00:21 UTCJul 22, 05:45 UTC5h 24m
2026-07-21 UAL1321 MIA → EWR Jul 21, 20:55 UTCJul 21, 21:50 UTC55m
2026-07-21 UAL1321 MIA → EWR Jul 21, 17:17 UTCJul 21, 21:43 UTC4h 26m
2026-07-21 UAL1321 MIA → EWR Jul 21, 17:15 UTCJul 21, 17:25 UTC10m
2026-07-21 UAL731 TPA → SFO Jul 21, 07:40 UTCJul 21, 07:55 UTC15m
2026-07-21 UAL731 TPA → SFO Jul 21, 02:45 UTCJul 21, 07:52 UTC5h 7m
2026-07-21 UAL731 TPA → SFO Jul 21, 02:45 UTCJul 21, 03:10 UTC25m
2026-07-20 UAL2862 SFO → DEN Jul 20, 19:05 UTCJul 20, 23:50 UTC4h 45m
2026-07-20 UAL2826 - Jul 20, 16:10 UTCJul 20, 17:30 UTC1h 20m
2026-07-20 UAL2084 ORD → SFO Jul 20, 13:00 UTCJul 20, 14:20 UTC1h 20m
2026-07-20 UAL8223 YVR → PDX Jul 20, 07:05 UTCJul 20, 11:35 UTC4h 30m
2026-07-20 UAL8223 YVR → PDX Jul 20, 06:53 UTCJul 20, 11:35 UTC4h 42m
2026-07-20 UAL693 PDX → SFO Jul 20, 04:10 UTCJul 20, 05:15 UTC1h 5m
2026-07-20 UAL693 PDX → SFO Jul 20, 00:15 UTCJul 20, 00:35 UTC20m
2026-07-19 UAL694 SFO → KOA Jul 19, 18:05 UTCJul 19, 18:45 UTC40m
2026-07-19 UAL611 CHS → EWR Jul 19, 10:55 UTCJul 19, 15:45 UTC4h 50m
2026-07-18 UAL1979 EWR → TPA Jul 18, 11:25 UTCJul 18, 13:45 UTC2h 20m
2026-07-18 UAL1979 EWR → TPA Jul 18, 11:19 UTCJul 18, 13:46 UTC2h 27m
2026-07-17 UAL1043 - Jul 17, 21:55 UTCJul 18, 02:14 UTC4h 20m
2026-07-17 UAL1042 - Jul 17, 20:15 UTCJul 17, 20:25 UTC10m
2026-07-17 UAL1042 - Jul 17, 16:10 UTCJul 17, 19:30 UTC3h 20m
2026-07-17 UAL2396 IAD → EWR Jul 17, 13:00 UTCJul 17, 13:45 UTC45m
2026-07-17 UAL1366 IAD → DEN Jul 17, 10:30 UTCJul 17, 11:20 UTC50m
2026-07-16 UAL569 EWR → EWR Jul 16, 23:49 UTCJul 17, 07:40 UTC7h 50m
2026-07-16 UAL2693 - Jul 16, 20:00 UTCJul 16, 21:35 UTC1h 35m
2026-07-16 UAL2693 CHS → EWR Jul 16, 19:56 UTCJul 16, 21:31 UTC1h 35m
2026-07-16 UAL1760 - Jul 16, 16:35 UTCJul 16, 17:54 UTC1h 20m
2026-07-16 UAL371 BNA → EWR Jul 16, 12:30 UTCJul 16, 14:20 UTC1h 50m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N37538 page for operator, model, and routing details .

Mode-S A44940 frequently asked

What is Mode-S code A44940?
A44940 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N37538.
Where is Mode-S A44940 registered?
Mode-S code A44940 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A44940 broadcasting right now?
Yes. Mode-S A44940 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A44940, octal 51044500, decimal 10,766,656.
What flights does A44940 operate?
Mode-S A44940 has broadcast 20 distinct callsigns, including UAL650, UAL2380, UAL701, UAL2491, UAL2404.