sensors Mode-S transponder

A41722

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N36272 · BOEING 737-800 · operated by UNITED AIRLINES INC

Hex
A41722
Octal
51013442
Decimal
10,753,826
Country
US
Tail
N36272
Type
B738
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
3
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A41722.

Country allocation

The ICAO 24-bit address A41722 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 3 distinct

Callsign Airline Flights Last seen
UAL3860 United Airlines 2 2026-04-13
UAL1280 - 2 2026-04-13
UAL426 - 1 2026-04-12

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL3860 DEN → IAH Apr 13, 19:55 UTCApr 13, 22:25 UTC2h 30m
2026-04-13 UAL3860 DEN → IAH Apr 13, 18:46 UTCApr 13, 21:22 UTC2h 36m
2026-04-13 UAL1280 - Apr 13, 02:00 UTCApr 13, 02:10 UTC10m
2026-04-13 UAL1280 - Apr 13, 00:00 UTCApr 13, 02:10 UTC2h 10m
2026-04-12 UAL426 - Apr 12, 17:15 UTCApr 12, 18:10 UTC55m

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 N36272 page for operator, model, and routing details .

Mode-S A41722 frequently asked

What is Mode-S code A41722?
A41722 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N36272.
Where is Mode-S A41722 registered?
Mode-S code A41722 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 A41722 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A41722, octal 51013442, decimal 10,753,826.
What flights does A41722 operate?
Mode-S A41722 has broadcast 3 distinct callsigns, including UAL3860, UAL1280, UAL426.