sensors Mode-S transponder

A0B81D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N14530 · operated by UNITED AIRLINES INC

Hex
A0B81D
Octal
50134035
Decimal
10,532,893
Country
US
Tail
N14530
Type
A21N
No current signal · last broadcast 1d ago
Flights observed
10
Distinct callsigns
6
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A0B81D.

Country allocation

The ICAO 24-bit address A0B81D 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
UAL2633 United Airlines 2 2026-04-13
UAL2436 United Airlines 2 2026-04-13
UAL2430 United Airlines 2 2026-04-13
UAL1113 - 2 2026-04-13
UAL675 - 1 2026-04-13
UAL2061 - 1 2026-04-12

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL675 - Apr 13, 23:25 UTCApr 13, 23:45 UTC20m
2026-04-13 UAL1113 - Apr 13, 19:50 UTCApr 13, 21:00 UTC1h 10m
2026-04-13 UAL1113 - Apr 13, 18:24 UTCApr 13, 20:44 UTC2h 20m
2026-04-13 UAL2430 ORD → ALB Apr 13, 15:50 UTCApr 13, 16:15 UTC25m
2026-04-13 UAL2430 ORD → ALB Apr 13, 14:03 UTCApr 13, 15:41 UTC1h 38m
2026-04-13 UAL2436 DEN → MSY Apr 13, 03:55 UTCApr 13, 04:20 UTC25m
2026-04-13 UAL2436 DEN → MSY Apr 13, 02:31 UTCApr 13, 04:53 UTC2h 22m
2026-04-13 UAL2633 PHL → IAH Apr 13, 00:25 UTCApr 13, 01:10 UTC45m
2026-04-12 UAL2633 PHL → IAH Apr 12, 23:55 UTCApr 13, 01:10 UTC1h 15m
2026-04-12 UAL2061 - Apr 12, 18:15 UTCApr 12, 20:00 UTC1h 45m

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 N14530 page for operator, model, and routing details .

Mode-S A0B81D frequently asked

What is Mode-S code A0B81D?
A0B81D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N14530.
Where is Mode-S A0B81D registered?
Mode-S code A0B81D 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 A0B81D 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 A0B81D, octal 50134035, decimal 10,532,893.
What flights does A0B81D operate?
Mode-S A0B81D has broadcast 6 distinct callsigns, including UAL2633, UAL2436, UAL2430, UAL1113, UAL675.