sensors Mode-S transponder

A0B1C9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N144CL · ROBINSON R-44 Raven · operated by STEWART JOSEPH W II

Hex
A0B1C9
Octal
50130711
Decimal
10,531,273
Country
US
Tail
N144CL
Type
R44
No current signal · last broadcast 21h ago
Flights observed
23
Distinct callsigns
1
Country
US
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S A0B1C9.

Country allocation

The ICAO 24-bit address A0B1C9 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
N144CL - 23 2026-06-25

Recent flights last 23

DateFlightRouteTakeoffLandingDuration
2026-06-25 N144CL - Jun 25, 22:20 UTCJun 25, 22:54 UTC35m
2026-06-24 N144CL - Jun 24, 02:30 UTCJun 24, 03:04 UTC35m
2026-06-24 N144CL - Jun 24, 01:39 UTCJun 24, 01:49 UTC10m
2026-06-24 N144CL - Jun 24, 00:20 UTCJun 24, 00:34 UTC15m
2026-06-19 N144CL - Jun 19, 19:04 UTCJun 19, 19:25 UTC20m
2026-06-17 N144CL - Jun 17, 16:10 UTCJun 17, 16:20 UTC10m
2026-06-16 N144CL - Jun 16, 19:19 UTCJun 16, 20:40 UTC1h 21m
2026-06-15 N144CL - Jun 15, 19:05 UTCJun 15, 19:25 UTC20m
2026-06-13 N144CL - Jun 13, 16:15 UTCJun 13, 16:35 UTC20m
2026-06-09 N144CL - Jun 9, 19:25 UTCJun 9, 20:25 UTC1h 0m
2026-06-09 N144CL - Jun 9, 13:30 UTCJun 9, 14:35 UTC1h 5m
2026-05-31 N144CL - May 31, 16:55 UTCMay 31, 17:05 UTC10m
2026-05-31 N144CL - May 31, 14:15 UTCMay 31, 14:40 UTC25m
2026-05-22 N144CL - May 22, 20:05 UTCMay 22, 20:25 UTC20m
2026-05-19 N144CL - May 19, 19:30 UTCMay 19, 19:45 UTC15m
2026-05-19 N144CL - May 19, 15:15 UTCMay 19, 15:35 UTC20m
2026-05-18 N144CL - May 18, 15:05 UTCMay 18, 15:15 UTC10m
2026-05-12 N144CL - May 12, 17:15 UTCMay 12, 17:35 UTC20m
2026-05-12 N144CL - May 12, 13:51 UTCMay 12, 14:25 UTC35m
2026-05-07 N144CL - May 7, 20:40 UTCMay 7, 20:55 UTC15m
2026-04-25 N144CL - Apr 25, 18:00 UTCApr 25, 18:40 UTC40m
2026-04-20 N144CL - Apr 20, 20:10 UTCApr 20, 20:40 UTC30m
2026-04-12 N144CL - Apr 12, 17:40 UTCApr 12, 18:25 UTC45m

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 N144CL page for operator, model, and routing details .

Mode-S A0B1C9 frequently asked

What is Mode-S code A0B1C9?
A0B1C9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N144CL.
Where is Mode-S A0B1C9 registered?
Mode-S code A0B1C9 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 A0B1C9 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 A0B1C9, octal 50130711, decimal 10,531,273.
What flights does A0B1C9 operate?
Mode-S A0B1C9 has broadcast 1 distinct callsign, including N144CL.