sensors Mode-S transponder

A44258

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N37372 · BOEING 737 MAX 8 · operated by UNITED AIRLINES INC

Hex
A44258
Octal
51041130
Decimal
10,764,888
Country
US
Tail
N37372
Type
B38M
Transponder active on ground
Flights observed
10
Distinct callsigns
8
Country
US
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S A44258.

Country allocation

The ICAO 24-bit address A44258 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 8 distinct

Callsign Airline Flights Last seen
UAL631 - 2 2026-04-12
UAL2188 United Airlines 2 2026-04-13
UAL784 - 1 2026-04-12
UAL2859 - 1 2026-04-13
UAL2398 - 1 2026-04-13
UAL1584 United Airlines 1 2026-04-13
UAL1343 United Airlines 1 2026-04-14
UAL1226 - 1 2026-04-12

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-14 UAL1343 EWR → TPA Apr 14, 10:20 UTCApr 14, 11:05 UTC45m
2026-04-13 UAL2398 - Apr 13, 21:15 UTCApr 13, 23:40 UTC2h 25m
2026-04-13 UAL2188 DEN → FLL Apr 13, 16:15 UTCApr 13, 19:40 UTC3h 25m
2026-04-13 UAL2188 DEN → FLL Apr 13, 16:00 UTCApr 13, 16:15 UTC15m
2026-04-13 UAL1584 SNA → SFO Apr 13, 13:30 UTCApr 13, 13:55 UTC25m
2026-04-13 UAL2859 - Apr 13, 01:50 UTCApr 13, 02:05 UTC15m
2026-04-12 UAL1226 - Apr 12, 23:55 UTCApr 13, 00:20 UTC25m
2026-04-12 UAL631 - Apr 12, 19:55 UTCApr 12, 20:15 UTC20m
2026-04-12 UAL631 DEN → DEN Apr 12, 19:40 UTCApr 12, 19:45 UTC5m
2026-04-12 UAL784 - Apr 12, 17:15 UTCApr 12, 17:20 UTC5m

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 N37372 page for operator, model, and routing details .

Mode-S A44258 frequently asked

What is Mode-S code A44258?
A44258 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N37372.
Where is Mode-S A44258 registered?
Mode-S code A44258 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 A44258 broadcasting right now?
Mode-S A44258 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A44258, octal 51041130, decimal 10,764,888.
What flights does A44258 operate?
Mode-S A44258 has broadcast 8 distinct callsigns, including UAL631, UAL2188, UAL784, UAL2859, UAL2398.