sensors Mode-S transponder

AD23F3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N946FD · BOEING 757-200 · operated by FEDERAL EXPRESS CORP

Hex
AD23F3
Octal
53221763
Decimal
11,346,931
Country
US
Tail
N946FD
Type
B752
No current signal · last broadcast 17h ago
Flights observed
5
Distinct callsigns
4
Country
US
Last broadcast
17h ago

Last known position

Most recent position reported by Mode-S AD23F3.

Country allocation

The ICAO 24-bit address AD23F3 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
FDX5503 - 2 2026-04-13
FDX5504 FedEx Express 1 2026-04-13
FDX1512 FedEx Express 1 2026-04-14
FDX114 - 1 2026-04-12

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 FDX1512 MEM → BMI Apr 14, 09:40 UTCApr 14, 10:30 UTC50m
2026-04-13 FDX5504 SAP → MIA Apr 13, 21:15 UTCApr 13, 21:35 UTC20m
2026-04-13 FDX5503 - Apr 13, 15:50 UTCApr 13, 16:05 UTC15m
2026-04-13 FDX5503 - Apr 13, 14:10 UTCApr 13, 16:28 UTC2h 18m
2026-04-12 FDX114 - Apr 12, 23:55 UTCApr 13, 00:20 UTC25m

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 N946FD page for operator, model, and routing details .

Mode-S AD23F3 frequently asked

What is Mode-S code AD23F3?
AD23F3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N946FD.
Where is Mode-S AD23F3 registered?
Mode-S code AD23F3 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 AD23F3 broadcasting right now?
No active broadcast right now. Last signal was 17h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AD23F3, octal 53221763, decimal 11,346,931.
What flights does AD23F3 operate?
Mode-S AD23F3 has broadcast 4 distinct callsigns, including FDX5503, FDX5504, FDX1512, FDX114.