sensors Mode-S transponder

A6CB9B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N537NA · operated by SETNA EXPRESS LLC

Hex
A6CB9B
Octal
51545633
Decimal
10,931,099
Country
US
Tail
N537NA
Type
GLF5
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A6CB9B.

Country allocation

The ICAO 24-bit address A6CB9B 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
EJM537 - 5 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 EJM537 - Apr 13, 08:50 UTCApr 13, 10:55 UTC2h 5m
2026-04-13 EJM537 - Apr 13, 04:20 UTCApr 13, 05:30 UTC1h 10m
2026-04-13 EJM537 - Apr 13, 03:55 UTCApr 13, 05:30 UTC1h 35m
2026-04-13 EJM537 - Apr 13, 03:10 UTCApr 13, 04:15 UTC1h 5m
2026-04-13 EJM537 - Apr 13, 01:05 UTCApr 13, 01:15 UTC10m

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 N537NA page for operator, model, and routing details .

Mode-S A6CB9B frequently asked

What is Mode-S code A6CB9B?
A6CB9B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N537NA.
Where is Mode-S A6CB9B registered?
Mode-S code A6CB9B 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 A6CB9B 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 A6CB9B, octal 51545633, decimal 10,931,099.
What flights does A6CB9B operate?
Mode-S A6CB9B has broadcast 1 distinct callsign, including EJM537.