sensors Mode-S transponder

A12799

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N17364 · BOEING 737 MAX 8 · operated by UNITED AIRLINES INC

Hex
A12799
Octal
50223631
Decimal
10,561,433
Country
US
Tail
N17364
Type
B38M
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
5
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A12799.

Country allocation

The ICAO 24-bit address A12799 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 5 distinct

Callsign Airline Flights Last seen
UAL2234 - 2 2026-04-13
UAL2671 - 1 2026-04-13
UAL2229 - 1 2026-04-13
UAL1986 - 1 2026-04-12
UAL1584 United Airlines 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL2671 TUS → DEN Apr 13, 21:00 UTCApr 13, 22:20 UTC1h 20m
2026-04-13 UAL1584 SNA → SFO Apr 13, 17:40 UTCApr 13, 19:20 UTC1h 40m
2026-04-13 UAL2234 - Apr 13, 15:50 UTCApr 13, 16:05 UTC15m
2026-04-13 UAL2234 SFO → DEN Apr 13, 13:55 UTCApr 13, 16:05 UTC2h 10m
2026-04-13 UAL2229 - Apr 13, 04:25 UTCApr 13, 05:00 UTC35m
2026-04-12 UAL1986 - Apr 12, 17:30 UTCApr 12, 17:55 UTC25m

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 N17364 page for operator, model, and routing details .

Mode-S A12799 frequently asked

What is Mode-S code A12799?
A12799 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N17364.
Where is Mode-S A12799 registered?
Mode-S code A12799 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 A12799 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 A12799, octal 50223631, decimal 10,561,433.
What flights does A12799 operate?
Mode-S A12799 has broadcast 5 distinct callsigns, including UAL2234, UAL2671, UAL2229, UAL1986, UAL1584.