sensors Mode-S transponder

A0631C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N124FS · operated by TVPX AIRCRAFT SOLUTIONS INC TRUSTEE

Hex
A0631C
Octal
50061434
Decimal
10,511,132
Country
US
Tail
N124FS
Type
PC24
Transponder active on ground
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A0631C.

Country allocation

The ICAO 24-bit address A0631C 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 1 distinct

Callsign Airline Flights Last seen
N124FS - 5 2026-06-11

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-11 N124FS - Jun 11, 13:50 UTCJun 11, 14:20 UTC30m
2026-05-28 N124FS - May 28, 13:55 UTCMay 28, 14:15 UTC20m
2026-05-27 N124FS - May 27, 14:00 UTCMay 27, 14:30 UTC30m
2026-05-23 N124FS - May 23, 14:45 UTCMay 23, 15:00 UTC15m
2026-05-23 N124FS - May 23, 11:45 UTCMay 23, 13:40 UTC1h 55m

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 N124FS page for operator, model, and routing details .

Mode-S A0631C frequently asked

What is Mode-S code A0631C?
A0631C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N124FS.
Where is Mode-S A0631C registered?
Mode-S code A0631C 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 A0631C broadcasting right now?
Mode-S A0631C is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0631C, octal 50061434, decimal 10,511,132.
What flights does A0631C operate?
Mode-S A0631C has broadcast 1 distinct callsign, including N124FS.