sensors Mode-S transponder

A023FF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N108SC · BELL 407 · operated by COUNTY OF SONOMA

Hex
A023FF
Octal
50021777
Decimal
10,494,975
Country
US
Tail
N108SC
Type
B407
No current signal · last broadcast 16m ago
Flights observed
51
Distinct callsigns
1
Country
US
Last broadcast
16m ago

Last known position

Most recent position reported by Mode-S A023FF.

Country allocation

The ICAO 24-bit address A023FF 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
N108SC - 50 2026-06-03

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-03 N108SC - Jun 3, 02:55 UTCJun 3, 03:40 UTC45m
2026-06-02 N108SC - Jun 2, 00:50 UTCJun 2, 01:50 UTC1h 0m
2026-06-01 N108SC - Jun 1, 03:35 UTCJun 1, 04:30 UTC55m
2026-05-31 N108SC - May 31, 23:15 UTCMay 31, 23:45 UTC30m
2026-05-29 N108SC - May 29, 02:55 UTCMay 29, 03:45 UTC50m
2026-05-27 N108SC - May 27, 23:35 UTCMay 28, 00:10 UTC35m
2026-05-27 N108SC - May 27, 03:24 UTCMay 27, 04:59 UTC1h 35m
2026-05-26 N108SC - May 26, 22:15 UTCMay 26, 22:25 UTC10m
2026-05-25 N108SC - May 25, 03:45 UTCMay 25, 05:00 UTC1h 15m
2026-05-24 N108SC - May 24, 00:20 UTCMay 24, 00:45 UTC25m
2026-05-22 N108SC - May 22, 23:00 UTCMay 23, 00:10 UTC1h 10m
2026-05-21 N108SC - May 21, 01:30 UTCMay 21, 02:05 UTC35m
2026-05-19 N108SC - May 19, 03:45 UTCMay 19, 04:25 UTC40m
2026-05-18 N108SC - May 18, 20:40 UTCMay 18, 21:05 UTC25m
2026-05-16 N108SC - May 16, 23:25 UTCMay 16, 23:35 UTC10m
2026-05-15 N108SC - May 15, 01:55 UTCMay 15, 02:25 UTC30m
2026-05-14 N108SC - May 14, 19:40 UTCMay 14, 21:05 UTC1h 25m
2026-05-14 N108SC - May 14, 03:40 UTCMay 14, 04:25 UTC45m
2026-05-13 N108SC - May 13, 03:30 UTCMay 13, 04:20 UTC50m
2026-05-11 N108SC - May 11, 01:00 UTCMay 11, 01:20 UTC20m
2026-05-10 N108SC - May 10, 21:59 UTCMay 10, 23:44 UTC1h 45m
2026-05-10 N108SC - May 10, 04:00 UTCMay 10, 05:10 UTC1h 10m
2026-05-09 N108SC - May 9, 22:10 UTCMay 9, 22:20 UTC10m
2026-05-09 - - May 9, 04:30 UTCMay 9, 04:45 UTC15m
2026-05-09 N108SC - May 9, 02:10 UTCMay 9, 02:25 UTC15m
2026-05-08 N108SC - May 8, 20:45 UTCMay 8, 22:15 UTC1h 30m
2026-05-08 N108SC - May 8, 03:24 UTCMay 8, 04:09 UTC45m
2026-05-06 N108SC - May 6, 20:50 UTCMay 6, 22:05 UTC1h 15m
2026-05-06 N108SC - May 6, 03:05 UTCMay 6, 04:35 UTC1h 30m
2026-05-05 N108SC - May 5, 23:05 UTCMay 5, 23:25 UTC20m
2026-05-02 N108SC - May 2, 03:35 UTCMay 2, 04:10 UTC35m
2026-05-01 N108SC - May 1, 22:45 UTCMay 1, 23:30 UTC45m
2026-05-01 N108SC - May 1, 03:50 UTCMay 1, 04:15 UTC25m
2026-04-30 N108SC - Apr 30, 23:45 UTCMay 1, 00:30 UTC45m
2026-04-30 N108SC - Apr 30, 03:40 UTCApr 30, 04:30 UTC50m
2026-04-29 N108SC - Apr 29, 17:55 UTCApr 29, 18:35 UTC40m
2026-04-29 N108SC - Apr 29, 03:30 UTCApr 29, 04:10 UTC40m
2026-04-28 N108SC - Apr 28, 02:55 UTCApr 28, 04:00 UTC1h 5m
2026-04-27 N108SC - Apr 27, 04:10 UTCApr 27, 04:30 UTC20m
2026-04-25 N108SC - Apr 25, 21:10 UTCApr 25, 21:35 UTC25m
2026-04-24 N108SC - Apr 24, 04:05 UTCApr 24, 04:45 UTC40m
2026-04-23 N108SC - Apr 23, 01:10 UTCApr 23, 02:30 UTC1h 20m
2026-04-22 N108SC - Apr 22, 03:50 UTCApr 22, 04:20 UTC30m
2026-04-22 N108SC - Apr 22, 01:30 UTCApr 22, 02:00 UTC30m
2026-04-20 N108SC - Apr 20, 03:30 UTCApr 20, 04:15 UTC45m
2026-04-19 N108SC - Apr 19, 23:20 UTCApr 19, 23:35 UTC15m
2026-04-18 N108SC - Apr 18, 23:25 UTCApr 18, 23:40 UTC15m
2026-04-18 N108SC - Apr 18, 15:00 UTCApr 18, 15:35 UTC35m
2026-04-18 N108SC - Apr 18, 04:00 UTCApr 18, 04:50 UTC50m
2026-04-15 N108SC - Apr 15, 00:30 UTCApr 15, 00:40 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 N108SC page for operator, model, and routing details .

Mode-S A023FF frequently asked

What is Mode-S code A023FF?
A023FF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N108SC.
Where is Mode-S A023FF registered?
Mode-S code A023FF 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 A023FF broadcasting right now?
No active broadcast right now. Last signal was 16m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A023FF, octal 50021777, decimal 10,494,975.
What flights does A023FF operate?
Mode-S A023FF has broadcast 1 distinct callsign, including N108SC.