sensors Mode-S transponder

A4DB9A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N412AM · DIAMOND DA-40 Club Star · operated by DA40 LLC

Hex
A4DB9A
Octal
51155632
Decimal
10,804,122
Country
US
Tail
N412AM
Type
DA40
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A4DB9A.

Country allocation

The ICAO 24-bit address A4DB9A 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
N412AM - 5 2026-04-27

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-27 N412AM - Apr 27, 23:50 UTCApr 28, 00:10 UTC20m
2026-04-18 N412AM - Apr 18, 22:00 UTCApr 18, 23:00 UTC1h 0m
2026-04-17 N412AM - Apr 17, 13:45 UTCApr 17, 15:10 UTC1h 24m
2026-04-15 N412AM - Apr 15, 23:45 UTCApr 16, 00:00 UTC15m
2026-04-12 N412AM - Apr 12, 17:45 UTCApr 12, 18:10 UTC25m

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 N412AM page for operator, model, and routing details .

Mode-S A4DB9A frequently asked

What is Mode-S code A4DB9A?
A4DB9A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N412AM.
Where is Mode-S A4DB9A registered?
Mode-S code A4DB9A 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 A4DB9A broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4DB9A, octal 51155632, decimal 10,804,122.
What flights does A4DB9A operate?
Mode-S A4DB9A has broadcast 1 distinct callsign, including N412AM.