sensors Mode-S transponder

A0B900

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N146AF · operated by CIRRUS DESIGN CORP

Hex
A0B900
Octal
50134400
Decimal
10,533,120
Country
US
Tail
N146AF
No current signal · last broadcast 21h ago
Flights observed
7
Distinct callsigns
1
Country
US
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S A0B900.

Country allocation

The ICAO 24-bit address A0B900 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
N146AF - 7 2026-04-17

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-17 N146AF - Apr 17, 19:25 UTCApr 17, 19:45 UTC20m
2026-04-17 N146AF - Apr 17, 18:05 UTCApr 17, 19:20 UTC1h 15m
2026-04-17 N146AF - Apr 17, 15:20 UTCApr 17, 15:50 UTC30m
2026-04-17 N146AF - Apr 17, 14:20 UTCApr 17, 15:15 UTC54m
2026-04-14 N146AF - Apr 14, 21:05 UTCApr 14, 22:50 UTC1h 45m
2026-04-14 N146AF - Apr 14, 15:25 UTCApr 14, 16:20 UTC55m
2026-04-12 N146AF - Apr 12, 17:15 UTCApr 12, 17:25 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 N146AF page for operator, model, and routing details .

Mode-S A0B900 frequently asked

What is Mode-S code A0B900?
A0B900 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N146AF.
Where is Mode-S A0B900 registered?
Mode-S code A0B900 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 A0B900 broadcasting right now?
No active broadcast right now. Last signal was 21h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0B900, octal 50134400, decimal 10,533,120.
What flights does A0B900 operate?
Mode-S A0B900 has broadcast 1 distinct callsign, including N146AF.