sensors Mode-S transponder

A1E4E9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N221BZ · AIRBUS A220-300 · operated by BANK OF UTAH TRUSTEE

Hex
A1E4E9
Octal
50362351
Decimal
10,609,897
Country
US
Tail
N221BZ
Type
BCS3
No current signal · last broadcast 23h ago
Flights observed
13
Distinct callsigns
7
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A1E4E9.

Country allocation

The ICAO 24-bit address A1E4E9 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 7 distinct

Callsign Airline Flights Last seen
MXY527 - 3 2026-04-13
MXY822 - 2 2026-04-12
MXY562 - 2 2026-04-13
MXY547 - 2 2026-04-13
MXY526 Breeze Airways 2 2026-04-13
MXY563 - 1 2026-04-13
MXY546 - 1 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-13 MXY563 - Apr 13, 22:35 UTCApr 13, 23:40 UTC1h 5m
2026-04-13 MXY562 - Apr 13, 20:05 UTCApr 13, 21:20 UTC1h 15m
2026-04-13 MXY562 - Apr 13, 17:15 UTCApr 13, 19:00 UTC1h 45m
2026-04-13 MXY547 - Apr 13, 15:50 UTCApr 13, 16:00 UTC10m
2026-04-13 MXY547 - Apr 13, 14:55 UTCApr 13, 16:00 UTC1h 5m
2026-04-13 MXY546 - Apr 13, 12:30 UTCApr 13, 13:45 UTC1h 15m
2026-04-13 MXY527 - Apr 13, 08:20 UTCApr 13, 10:15 UTC1h 55m
2026-04-13 MXY527 - Apr 13, 07:55 UTCApr 13, 10:15 UTC2h 20m
2026-04-13 MXY527 - Apr 13, 06:00 UTCApr 13, 08:15 UTC2h 15m
2026-04-13 MXY526 LAS → SBD Apr 13, 00:20 UTCApr 13, 03:50 UTC3h 30m
2026-04-12 MXY526 LAS → SBD Apr 12, 23:55 UTCApr 13, 03:50 UTC3h 55m
2026-04-12 MXY822 - Apr 12, 19:15 UTCApr 12, 20:15 UTC1h 0m
2026-04-12 MXY822 - Apr 12, 17:15 UTCApr 12, 18:10 UTC55m

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 N221BZ page for operator, model, and routing details .

Mode-S A1E4E9 frequently asked

What is Mode-S code A1E4E9?
A1E4E9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N221BZ.
Where is Mode-S A1E4E9 registered?
Mode-S code A1E4E9 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 A1E4E9 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 A1E4E9, octal 50362351, decimal 10,609,897.
What flights does A1E4E9 operate?
Mode-S A1E4E9 has broadcast 7 distinct callsigns, including MXY527, MXY822, MXY562, MXY547, MXY526.