sensors Mode-S transponder

A30121

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N293FE · BOEING 767-300 · operated by FEDERAL EXPRESS CORP

Hex
A30121
Octal
50600441
Decimal
10,682,657
Country
US
Tail
N293FE
Type
B763
No current signal · last broadcast 22h ago
Flights observed
3
Distinct callsigns
3
Country
US
Last broadcast
22h ago

Last known position

Most recent position reported by Mode-S A30121.

Country allocation

The ICAO 24-bit address A30121 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 3 distinct

Callsign Airline Flights Last seen
FDX58 FedEx Express 1 2026-04-14
FDX57 - 1 2026-04-12
FDX142 - 1 2026-04-14

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-14 FDX142 - Apr 14, 09:50 UTCApr 14, 11:05 UTC1h 15m
2026-04-14 FDX58 BQN → MEM Apr 14, 05:15 UTCApr 14, 05:30 UTC15m
2026-04-12 FDX57 - Apr 12, 23:55 UTCApr 13, 00:05 UTC10m

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 N293FE page for operator, model, and routing details .

Mode-S A30121 frequently asked

What is Mode-S code A30121?
A30121 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N293FE.
Where is Mode-S A30121 registered?
Mode-S code A30121 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 A30121 broadcasting right now?
No active broadcast right now. Last signal was 22h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A30121, octal 50600441, decimal 10,682,657.
What flights does A30121 operate?
Mode-S A30121 has broadcast 3 distinct callsigns, including FDX58, FDX57, FDX142.