sensors Mode-S transponder

ACC9FF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N923HA · CESSNA 525B Citation CJ3 · operated by TVPX AIRCRAFT SOLUTIONS INC TRUSTEE

Hex
ACC9FF
Octal
53144777
Decimal
11,323,903
Country
US
Tail
N923HA
Type
C25B
No current signal · last broadcast 21h ago
Flights observed
8
Distinct callsigns
1
Country
US
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S ACC9FF.

Country allocation

The ICAO 24-bit address ACC9FF 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
N923HA - 8 2026-05-05

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-05-05 N923HA BTR → NEW May 5, 18:20 UTCMay 5, 18:45 UTC25m
2026-05-05 N923HA - May 5, 14:20 UTCMay 5, 17:30 UTC3h 10m
2026-04-28 N923HA - Apr 28, 23:20 UTCApr 29, 00:40 UTC1h 20m
2026-04-28 N923HA - Apr 28, 18:50 UTCApr 28, 19:40 UTC50m
2026-04-27 N923HA - Apr 27, 23:40 UTCApr 28, 00:30 UTC50m
2026-04-27 N923HA - Apr 27, 14:20 UTCApr 27, 15:10 UTC50m
2026-04-16 N923HA - Apr 16, 19:15 UTCApr 16, 19:50 UTC35m
2026-04-13 N923HA - Apr 13, 14:20 UTCApr 13, 15:05 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 N923HA page for operator, model, and routing details .

Mode-S ACC9FF frequently asked

What is Mode-S code ACC9FF?
ACC9FF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N923HA.
Where is Mode-S ACC9FF registered?
Mode-S code ACC9FF 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 ACC9FF 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 ACC9FF, octal 53144777, decimal 11,323,903.
What flights does ACC9FF operate?
Mode-S ACC9FF has broadcast 1 distinct callsign, including N923HA.