sensors Mode-S transponder

A2666C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N254AT · PIPER PA-44 Seminole · operated by AIRLINE TRANSPORT PROFESSIONALS CORP OF USA

Hex
A2666C
Octal
50463154
Decimal
10,643,052
Country
US
Tail
N254AT
Type
PA44
No current signal · last broadcast 1d ago
Flights observed
3
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A2666C.

Country allocation

The ICAO 24-bit address A2666C 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
CXK1050 - 3 2026-04-13

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-13 CXK1050 - Apr 13, 21:30 UTCApr 13, 22:15 UTC45m
2026-04-12 CXK1050 - Apr 12, 19:25 UTCApr 12, 20:15 UTC50m
2026-04-12 CXK1050 - 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 N254AT page for operator, model, and routing details .

Mode-S A2666C frequently asked

What is Mode-S code A2666C?
A2666C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N254AT.
Where is Mode-S A2666C registered?
Mode-S code A2666C 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 A2666C broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2666C, octal 50463154, decimal 10,643,052.
What flights does A2666C operate?
Mode-S A2666C has broadcast 1 distinct callsign, including CXK1050.