sensors Mode-S transponder

A0B866

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N14553 · AIRBUS A-321neo · operated by UNITED AIRLINES INC

Hex
A0B866
Octal
50134146
Decimal
10,532,966
Country
US
Tail
N14553
Type
A21N
No current signal · last broadcast 23h ago
Flights observed
9
Distinct callsigns
6
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A0B866.

Country allocation

The ICAO 24-bit address A0B866 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 6 distinct

Callsign Airline Flights Last seen
UAL2113 - 2 2026-04-13
UAL1638 - 2 2026-04-13
UAL1100 United Airlines 2 2026-04-13
UAL347 - 1 2026-04-12
UAL1967 United Airlines 1 2026-04-13
UAL1865 - 1 2026-04-12

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL1967 DEN → MSN Apr 13, 23:15 UTCApr 13, 23:45 UTC30m
2026-04-13 UAL2113 - Apr 13, 19:50 UTCApr 13, 21:05 UTC1h 15m
2026-04-13 UAL2113 - Apr 13, 17:45 UTCApr 13, 20:10 UTC2h 25m
2026-04-13 UAL1638 - Apr 13, 15:50 UTCApr 13, 16:10 UTC20m
2026-04-13 UAL1638 - Apr 13, 14:03 UTCApr 13, 16:05 UTC2h 2m
2026-04-13 UAL1100 EWR → MIA Apr 13, 03:55 UTCApr 13, 04:05 UTC10m
2026-04-13 UAL1100 EWR → MIA Apr 13, 00:35 UTCApr 13, 04:05 UTC3h 30m
2026-04-12 UAL347 - Apr 12, 19:45 UTCApr 12, 20:15 UTC30m
2026-04-12 UAL1865 - Apr 12, 17:15 UTCApr 12, 17:50 UTC35m

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 N14553 page for operator, model, and routing details .

Mode-S A0B866 frequently asked

What is Mode-S code A0B866?
A0B866 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N14553.
Where is Mode-S A0B866 registered?
Mode-S code A0B866 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 A0B866 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 A0B866, octal 50134146, decimal 10,532,966.
What flights does A0B866 operate?
Mode-S A0B866 has broadcast 6 distinct callsigns, including UAL2113, UAL1638, UAL1100, UAL347, UAL1967.