sensors Mode-S transponder

AC9B54

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N911KS · AIRBUS HELICOPTERS EC-135/635 · operated by MED-TRANS CORP

Hex
AC9B54
Octal
53115524
Decimal
11,311,956
Country
US
Tail
N911KS
Type
EC35
No current signal · last broadcast 6d ago
Flights observed
37
Distinct callsigns
1
Country
US
Last broadcast
6d ago

Last known position

Most recent position reported by Mode-S AC9B54.

Country allocation

The ICAO 24-bit address AC9B54 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
N911KS - 37 2026-05-27

Recent flights last 37

DateFlightRouteTakeoffLandingDuration
2026-05-27 N911KS - May 27, 19:55 UTCMay 27, 20:50 UTC55m
2026-05-21 N911KS - May 21, 18:15 UTCMay 21, 19:10 UTC55m
2026-05-21 N911KS - May 21, 17:15 UTCMay 21, 17:35 UTC20m
2026-05-21 N911KS - May 21, 15:40 UTCMay 21, 16:35 UTC55m
2026-05-20 N911KS - May 20, 16:55 UTCMay 20, 17:15 UTC20m
2026-05-20 N911KS - May 20, 16:05 UTCMay 20, 16:25 UTC20m
2026-05-20 N911KS - May 20, 14:55 UTCMay 20, 15:20 UTC25m
2026-05-20 N911KS - May 20, 13:45 UTCMay 20, 14:00 UTC15m
2026-05-19 N911KS - May 19, 21:05 UTCMay 19, 21:55 UTC50m
2026-05-19 N911KS - May 19, 19:25 UTCMay 19, 19:35 UTC10m
2026-05-19 N911KS - May 19, 17:45 UTCMay 19, 18:00 UTC15m
2026-05-19 N911KS - May 19, 15:55 UTCMay 19, 16:05 UTC10m
2026-05-18 N911KS - May 18, 22:05 UTCMay 18, 22:55 UTC50m
2026-05-18 N911KS - May 18, 06:35 UTCMay 18, 07:05 UTC30m
2026-05-18 N911KS - May 18, 05:15 UTCMay 18, 06:01 UTC45m
2026-05-17 N911KS - May 17, 06:05 UTCMay 17, 06:15 UTC10m
2026-05-16 N911KS - May 16, 19:50 UTCMay 16, 20:50 UTC1h 0m
2026-05-16 N911KS - May 16, 18:40 UTCMay 16, 19:05 UTC25m
2026-05-16 N911KS - May 16, 04:15 UTCMay 16, 04:25 UTC10m
2026-05-16 N911KS - May 16, 00:10 UTCMay 16, 00:20 UTC10m
2026-05-15 N911KS - May 15, 21:55 UTCMay 15, 22:05 UTC10m
2026-05-15 N911KS - May 15, 21:05 UTCMay 15, 21:20 UTC15m
2026-05-15 N911KS - May 15, 19:05 UTCMay 15, 20:05 UTC1h 0m
2026-05-13 N911KS - May 13, 18:55 UTCMay 13, 19:05 UTC10m
2026-05-09 N911KS - May 9, 19:30 UTCMay 9, 21:25 UTC1h 55m
2026-05-08 N911KS - May 8, 14:25 UTCMay 8, 14:50 UTC25m
2026-04-28 N911KS - Apr 28, 21:45 UTCApr 28, 22:55 UTC1h 10m
2026-04-28 N911KS - Apr 28, 19:45 UTCApr 28, 20:45 UTC1h 0m
2026-04-24 N911KS - Apr 24, 13:15 UTCApr 24, 14:20 UTC1h 5m
2026-04-24 N911KS - Apr 24, 12:05 UTCApr 24, 12:30 UTC25m
2026-04-24 N911KS - Apr 24, 11:00 UTCApr 24, 11:10 UTC10m
2026-04-24 N911KS - Apr 24, 04:30 UTCApr 24, 04:40 UTC10m
2026-04-22 N911KS - Apr 22, 05:40 UTCApr 22, 05:55 UTC15m
2026-04-22 N911KS - Apr 22, 04:00 UTCApr 22, 04:10 UTC10m
2026-04-21 N911KS - Apr 21, 23:30 UTCApr 21, 23:40 UTC10m
2026-04-21 N911KS - Apr 21, 22:00 UTCApr 21, 22:20 UTC20m
2026-04-21 N911KS - Apr 21, 20:40 UTCApr 21, 20:55 UTC15m

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 N911KS page for operator, model, and routing details .

Mode-S AC9B54 frequently asked

What is Mode-S code AC9B54?
AC9B54 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N911KS.
Where is Mode-S AC9B54 registered?
Mode-S code AC9B54 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 AC9B54 broadcasting right now?
No active broadcast right now. Last signal was 6d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC9B54, octal 53115524, decimal 11,311,956.
What flights does AC9B54 operate?
Mode-S AC9B54 has broadcast 1 distinct callsign, including N911KS.