sensors Mode-S transponder

A0B840

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N14540 · operated by WILMINGTON TRUST CO TRUSTEE

Hex
A0B840
Octal
50134100
Decimal
10,532,928
Country
US
Tail
N14540
Type
A21N
Broadcasting now · callsign UAL2607 · 34,000 ft
Flights observed
14
Distinct callsigns
6
Country
US
Last broadcast
1d ago

Current position

A0B840 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A0B840 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
UAL2295 - 3 2026-04-13
UAL1754 United Airlines 3 2026-04-13
UAL1525 - 3 2026-04-13
UAL374 United Airlines 2 2026-04-12
UAL1363 United Airlines 2 2026-04-13
UAL1941 United Airlines 1 2026-04-12

Recent flights last 14

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL1363 SJC → DEN Apr 13, 19:50 UTCApr 13, 23:20 UTC3h 30m
2026-04-13 UAL1363 SJC → DEN Apr 13, 19:05 UTCApr 13, 20:10 UTC1h 5m
2026-04-13 UAL1525 - Apr 13, 16:15 UTCApr 13, 16:45 UTC30m
2026-04-13 UAL1525 - Apr 13, 15:50 UTCApr 13, 16:45 UTC55m
2026-04-13 UAL1525 - Apr 13, 14:45 UTCApr 13, 16:15 UTC1h 30m
2026-04-13 UAL2295 - Apr 13, 12:20 UTCApr 13, 12:40 UTC20m
2026-04-13 UAL2295 - Apr 13, 11:55 UTCApr 13, 12:40 UTC45m
2026-04-13 UAL2295 - Apr 13, 11:05 UTCApr 13, 12:15 UTC1h 10m
2026-04-13 UAL1754 MSN → ORD Apr 13, 04:20 UTCApr 13, 05:25 UTC1h 5m
2026-04-13 UAL1754 MSN → ORD Apr 13, 03:55 UTCApr 13, 05:25 UTC1h 30m
2026-04-13 UAL1754 MSN → ORD Apr 13, 02:00 UTCApr 13, 04:15 UTC2h 15m
2026-04-12 UAL374 EWR → PBI Apr 12, 23:55 UTCApr 13, 00:05 UTC10m
2026-04-12 UAL374 EWR → PBI Apr 12, 20:05 UTCApr 12, 20:15 UTC10m
2026-04-12 UAL1941 IAD → EWR Apr 12, 17:15 UTCApr 12, 18:00 UTC45m

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 N14540 page for operator, model, and routing details .

Mode-S A0B840 frequently asked

What is Mode-S code A0B840?
A0B840 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N14540.
Where is Mode-S A0B840 registered?
Mode-S code A0B840 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 A0B840 broadcasting right now?
Yes. Mode-S A0B840 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0B840, octal 50134100, decimal 10,532,928.
What flights does A0B840 operate?
Mode-S A0B840 has broadcast 6 distinct callsigns, including UAL2295, UAL1754, UAL1525, UAL374, UAL1363.