sensors Mode-S transponder

A9DAAC

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N734HX · CESSNA T206 Turbo Stationair · operated by WATERS AERO- MARINE INC DBA, PENOBSCOT ISLAND AIR

Hex
A9DAAC
Octal
52355254
Decimal
11,131,564
Country
US
Tail
N734HX
Type
T206
No current signal · last broadcast 2d ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A9DAAC.

Country allocation

The ICAO 24-bit address A9DAAC 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
N734HX - 1 2026-04-12

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-12 N734HX - Apr 12, 17:15 UTCApr 12, 17:30 UTC15m

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 N734HX page for operator, model, and routing details .

Mode-S A9DAAC frequently asked

What is Mode-S code A9DAAC?
A9DAAC is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N734HX.
Where is Mode-S A9DAAC registered?
Mode-S code A9DAAC 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 A9DAAC broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9DAAC, octal 52355254, decimal 11,131,564.
What flights does A9DAAC operate?
Mode-S A9DAAC has broadcast 1 distinct callsign, including N734HX.