sensors Mode-S transponder

A2CB9E

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N27997 · BOEING 787-9 Dreamliner · operated by BOEING CO

Hex
A2CB9E
Octal
50545636
Decimal
10,668,958
Country
US
Tail
N27997
Type
B789
No current signal · last broadcast 23h ago
Flights observed
7
Distinct callsigns
2
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A2CB9E.

Country allocation

The ICAO 24-bit address A2CB9E 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 2 distinct

Callsign Airline Flights Last seen
UAL761 United Airlines 4 2026-04-13
UAL760 - 3 2026-04-13

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL761 MUC → DEN Apr 13, 19:50 UTCApr 13, 23:45 UTC3h 55m
2026-04-13 UAL761 MUC → DEN Apr 13, 16:15 UTCApr 13, 20:10 UTC3h 55m
2026-04-13 UAL761 MUC → DEN Apr 13, 15:50 UTCApr 13, 16:40 UTC50m
2026-04-13 UAL761 MUC → DEN Apr 13, 14:31 UTCApr 14, 00:42 UTC10h 11m
2026-04-13 UAL760 - Apr 13, 09:25 UTCApr 13, 11:35 UTC2h 10m
2026-04-13 UAL760 - Apr 13, 03:55 UTCApr 13, 04:20 UTC25m
2026-04-13 UAL760 - Apr 13, 02:40 UTCApr 13, 04:15 UTC1h 35m

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 N27997 page for operator, model, and routing details .

Mode-S A2CB9E frequently asked

What is Mode-S code A2CB9E?
A2CB9E is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N27997.
Where is Mode-S A2CB9E registered?
Mode-S code A2CB9E 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 A2CB9E broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2CB9E, octal 50545636, decimal 10,668,958.
What flights does A2CB9E operate?
Mode-S A2CB9E has broadcast 2 distinct callsigns, including UAL761, UAL760.