sensors Mode-S transponder

A6ED3B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N54525 · AIRBUS A-321neo · operated by UNITED AIRLINES INC

Hex
A6ED3B
Octal
51566473
Decimal
10,939,707
Country
US
Tail
N54525
Type
A21N
No current signal · last broadcast 1d ago
Flights observed
9
Distinct callsigns
4
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A6ED3B.

Country allocation

The ICAO 24-bit address A6ED3B 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 4 distinct

Callsign Airline Flights Last seen
UAL1941 United Airlines 4 2026-04-13
UAL704 United Airlines 2 2026-04-13
UAL1967 United Airlines 2 2026-04-13
UAL2113 - 1 2026-04-12

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL704 IAH → EWR Apr 13, 20:03 UTCApr 13, 21:47 UTC1h 44m
2026-04-13 UAL704 IAH → EWR Apr 13, 20:03 UTCApr 13, 21:47 UTC1h 44m
2026-04-13 UAL1941 IAD → EWR Apr 13, 16:15 UTCApr 13, 17:35 UTC1h 20m
2026-04-13 UAL1941 IAD → EWR Apr 13, 15:50 UTCApr 13, 17:35 UTC1h 45m
2026-04-13 UAL1941 IAD → EWR Apr 13, 14:19 UTCApr 13, 17:42 UTC3h 23m
2026-04-13 UAL1941 IAD → EWR Apr 13, 14:19 UTCApr 13, 17:09 UTC2h 50m
2026-04-13 UAL1967 DEN → MSN Apr 13, 00:20 UTCApr 13, 03:40 UTC3h 20m
2026-04-12 UAL1967 DEN → MSN Apr 12, 23:55 UTCApr 13, 03:40 UTC3h 45m
2026-04-12 UAL2113 - Apr 12, 18:05 UTCApr 12, 20:15 UTC2h 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 N54525 page for operator, model, and routing details .

Mode-S A6ED3B frequently asked

What is Mode-S code A6ED3B?
A6ED3B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N54525.
Where is Mode-S A6ED3B registered?
Mode-S code A6ED3B 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 A6ED3B 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 A6ED3B, octal 51566473, decimal 10,939,707.
What flights does A6ED3B operate?
Mode-S A6ED3B has broadcast 4 distinct callsigns, including UAL1941, UAL704, UAL1967, UAL2113.