sensors Mode-S transponder

A9FDBB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N743AM · BELL 407 · operated by TEXTRON FINANCIAL CORP

Hex
A9FDBB
Octal
52376673
Decimal
11,140,539
Country
US
Tail
N743AM
Type
B407
No current signal · last broadcast 22h ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
22h ago

Last known position

Most recent position reported by Mode-S A9FDBB.

Country allocation

The ICAO 24-bit address A9FDBB 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
N743AM - 11 2026-04-27

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-27 N743AM - Apr 27, 04:05 UTCApr 27, 04:15 UTC10m
2026-04-27 N743AM - Apr 27, 02:15 UTCApr 27, 02:25 UTC10m
2026-04-25 N743AM - Apr 25, 14:25 UTCApr 25, 14:35 UTC10m
2026-04-25 N743AM - Apr 25, 13:35 UTCApr 25, 13:45 UTC10m
2026-04-23 N743AM - Apr 23, 10:30 UTCApr 23, 10:50 UTC20m
2026-04-23 N743AM - Apr 23, 10:01 UTCApr 23, 10:15 UTC15m
2026-04-23 N743AM - Apr 23, 08:40 UTCApr 23, 09:15 UTC35m
2026-04-22 N743AM - Apr 22, 16:30 UTCApr 22, 16:40 UTC10m
2026-04-22 N743AM - Apr 22, 14:40 UTCApr 22, 14:50 UTC10m
2026-04-19 N743AM - Apr 19, 02:05 UTCApr 19, 02:55 UTC50m
2026-04-18 N743AM - Apr 18, 22:55 UTCApr 18, 23:30 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 N743AM page for operator, model, and routing details .

Mode-S A9FDBB frequently asked

What is Mode-S code A9FDBB?
A9FDBB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N743AM.
Where is Mode-S A9FDBB registered?
Mode-S code A9FDBB 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 A9FDBB broadcasting right now?
No active broadcast right now. Last signal was 22h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9FDBB, octal 52376673, decimal 11,140,539.
What flights does A9FDBB operate?
Mode-S A9FDBB has broadcast 1 distinct callsign, including N743AM.