sensors Mode-S transponder

A9D66F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N733CN · CESSNA 172 Skyhawk · operated by CHRISTIANSEN AVIATION LLC

Hex
A9D66F
Octal
52353157
Decimal
11,130,479
Country
US
Tail
N733CN
Type
C172
No current signal · last broadcast 1d ago
Flights observed
2
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A9D66F.

Country allocation

The ICAO 24-bit address A9D66F 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
AUB130 - 2 2026-04-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-13 AUB130 AUO → AUO Apr 13, 20:25 UTCApr 13, 21:35 UTC1h 10m
2026-04-13 AUB130 AUO → AUO Apr 13, 18:00 UTCApr 13, 19:20 UTC1h 20m

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 N733CN page for operator, model, and routing details .

Mode-S A9D66F frequently asked

What is Mode-S code A9D66F?
A9D66F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N733CN.
Where is Mode-S A9D66F registered?
Mode-S code A9D66F 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 A9D66F 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 A9D66F, octal 52353157, decimal 11,130,479.
What flights does A9D66F operate?
Mode-S A9D66F has broadcast 1 distinct callsign, including AUB130.