sensors Mode-S transponder

A23F5D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N244FE · operated by FEDERAL EXPRESS CORP

Hex
A23F5D
Octal
50437535
Decimal
10,633,053
Country
US
Tail
N244FE
No current signal · last broadcast 7d ago
Flights observed
5
Distinct callsigns
2
Country
US
Last broadcast
7d ago

Last known position

Most recent position reported by Mode-S A23F5D.

Country allocation

The ICAO 24-bit address A23F5D 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 2 distinct

Callsign Airline Flights Last seen
BOE705 - 4 2026-05-26
FDX9050 FedEx Express 1 2026-05-28

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-28 FDX9050 MEM → ARA May 28, 20:50 UTCMay 29, 00:40 UTC3h 50m
2026-05-26 BOE705 - May 26, 17:44 UTCMay 26, 20:50 UTC3h 5m
2026-05-21 BOE705 - May 21, 15:45 UTCMay 21, 17:10 UTC1h 25m
2026-05-17 BOE705 PAE → PAE May 17, 17:40 UTCMay 17, 19:45 UTC2h 5m
2026-05-08 BOE705 - May 8, 16:55 UTCMay 8, 19:45 UTC2h 50m

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 N244FE page for operator, model, and routing details .

Mode-S A23F5D frequently asked

What is Mode-S code A23F5D?
A23F5D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N244FE.
Where is Mode-S A23F5D registered?
Mode-S code A23F5D 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 A23F5D broadcasting right now?
No active broadcast right now. Last signal was 7d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A23F5D, octal 50437535, decimal 10,633,053.
What flights does A23F5D operate?
Mode-S A23F5D has broadcast 2 distinct callsigns, including BOE705, FDX9050.