sensors Mode-S transponder

A0B820

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N14533 · AIRBUS A-321neo · operated by UNITED AIRLINES INC

Hex
A0B820
Octal
50134040
Decimal
10,532,896
Country
US
Tail
N14533
Type
A21N
No current signal · last broadcast 1d ago
Flights observed
11
Distinct callsigns
6
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A0B820.

Country allocation

The ICAO 24-bit address A0B820 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
UAL661 United Airlines 3 2026-04-13
UAL405 - 2 2026-04-13
UAL1659 - 2 2026-04-12
UAL1339 - 2 2026-04-13
UAL360 United Airlines 1 2026-04-13
UAL1667 United Airlines 1 2026-04-12

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL360 DFW → EWR Apr 13, 20:20 UTCApr 13, 22:05 UTC1h 45m
2026-04-13 UAL405 - Apr 13, 16:15 UTCApr 13, 18:05 UTC1h 50m
2026-04-13 UAL405 - Apr 13, 15:55 UTCApr 13, 16:15 UTC20m
2026-04-13 UAL1339 - Apr 13, 12:20 UTCApr 13, 13:50 UTC1h 30m
2026-04-13 UAL1339 - Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 UAL661 ORD → EWR Apr 13, 04:20 UTCApr 13, 07:40 UTC3h 20m
2026-04-13 UAL661 ORD → EWR Apr 13, 03:55 UTCApr 13, 07:40 UTC3h 45m
2026-04-13 UAL661 ORD → EWR Apr 13, 03:40 UTCApr 13, 04:15 UTC35m
2026-04-12 UAL1667 CUN → ORD Apr 12, 23:55 UTCApr 13, 00:15 UTC20m
2026-04-12 UAL1659 - Apr 12, 19:10 UTCApr 12, 19:25 UTC15m
2026-04-12 UAL1659 - Apr 12, 17:15 UTCApr 12, 18:25 UTC1h 10m

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 N14533 page for operator, model, and routing details .

Mode-S A0B820 frequently asked

What is Mode-S code A0B820?
A0B820 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N14533.
Where is Mode-S A0B820 registered?
Mode-S code A0B820 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 A0B820 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 A0B820, octal 50134040, decimal 10,532,896.
What flights does A0B820 operate?
Mode-S A0B820 has broadcast 6 distinct callsigns, including UAL661, UAL405, UAL1659, UAL1339, UAL360.