sensors Mode-S transponder

A261C9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N25233 · CESSNA 152 · operated by HILLSBORO AERO ACADEMY LLC

Hex
A261C9
Octal
50460711
Decimal
10,641,865
Country
US
Tail
N25233
Type
C152
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 A261C9.

Country allocation

The ICAO 24-bit address A261C9 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
N25233 - 3 2026-04-13

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-13 N25233 RDM → RDM Apr 13, 16:15 UTCApr 13, 16:25 UTC10m
2026-04-13 N25233 RDM → RDM Apr 13, 15:50 UTCApr 13, 16:25 UTC35m
2026-04-13 N25233 RDM → RDM Apr 13, 15:40 UTCApr 13, 16:15 UTC35m

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 N25233 page for operator, model, and routing details .

Mode-S A261C9 frequently asked

What is Mode-S code A261C9?
A261C9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N25233.
Where is Mode-S A261C9 registered?
Mode-S code A261C9 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 A261C9 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 A261C9, octal 50460711, decimal 10,641,865.
What flights does A261C9 operate?
Mode-S A261C9 has broadcast 1 distinct callsign, including N25233.