sensors Mode-S transponder

AC9C2B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N911UG · AIRBUS HELICOPTERS EC-135/635 · operated by ACM EL TRUST SUBSIDIARY LLC

Hex
AC9C2B
Octal
53116053
Decimal
11,312,171
Country
US
Tail
N911UG
Type
EC35
No current signal · last broadcast 2d ago
Flights observed
34
Distinct callsigns
1
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S AC9C2B.

Country allocation

The ICAO 24-bit address AC9C2B 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
N911UG - 34 2026-06-03

Recent flights last 34

DateFlightRouteTakeoffLandingDuration
2026-06-03 N911UG - Jun 3, 21:35 UTCJun 3, 21:55 UTC20m
2026-06-03 N911UG - Jun 3, 18:50 UTCJun 3, 19:20 UTC30m
2026-05-22 N911UG DNL → CUB May 22, 02:25 UTCMay 22, 03:10 UTC45m
2026-05-22 N911UG - May 22, 00:40 UTCMay 22, 01:45 UTC1h 5m
2026-05-20 N911UG - May 20, 21:55 UTCMay 20, 22:30 UTC35m
2026-05-20 N911UG - May 20, 20:40 UTCMay 20, 21:20 UTC40m
2026-05-20 N911UG CDN → CDN May 20, 08:00 UTCMay 20, 09:25 UTC1h 25m
2026-05-20 N911UG - May 20, 00:20 UTCMay 20, 02:40 UTC2h 20m
2026-05-19 N911UG - May 19, 06:00 UTCMay 19, 07:30 UTC1h 30m
2026-05-17 N911UG - May 17, 23:45 UTCMay 18, 01:30 UTC1h 45m
2026-05-17 N911UG - May 17, 20:01 UTCMay 17, 20:40 UTC40m
2026-05-17 N911UG - May 17, 19:05 UTCMay 17, 19:15 UTC10m
2026-05-14 N911UG - May 14, 23:10 UTCMay 15, 01:30 UTC2h 20m
2026-05-08 N911UG - May 8, 06:35 UTCMay 8, 06:59 UTC25m
2026-05-08 N911UG - May 8, 04:54 UTCMay 8, 05:54 UTC1h 0m
2026-05-06 N911UG - May 6, 16:55 UTCMay 6, 17:05 UTC10m
2026-05-06 N911UG - May 6, 06:45 UTCMay 6, 07:30 UTC45m
2026-05-06 N911UG - May 6, 05:15 UTCMay 6, 06:10 UTC55m
2026-04-30 N911UG - Apr 30, 19:10 UTCApr 30, 19:50 UTC40m
2026-04-30 N911UG - Apr 30, 17:20 UTCApr 30, 18:05 UTC45m
2026-04-30 N911UG - Apr 30, 00:50 UTCApr 30, 01:10 UTC20m
2026-04-29 N911UG - Apr 29, 23:10 UTCApr 29, 23:25 UTC15m
2026-04-27 N911UG - Apr 27, 02:10 UTCApr 27, 02:25 UTC15m
2026-04-26 N911UG - Apr 26, 23:50 UTCApr 27, 00:50 UTC1h 0m
2026-04-26 N911UG - Apr 26, 23:05 UTCApr 26, 23:20 UTC15m
2026-04-25 N911UG - Apr 25, 10:55 UTCApr 25, 11:10 UTC15m
2026-04-25 N911UG - Apr 25, 03:35 UTCApr 25, 04:35 UTC1h 0m
2026-04-25 N911UG - Apr 25, 01:45 UTCApr 25, 02:05 UTC20m
2026-04-22 N911UG - Apr 22, 05:55 UTCApr 22, 07:10 UTC1h 15m
2026-04-19 N911UG - Apr 19, 02:35 UTCApr 19, 03:25 UTC50m
2026-04-19 N911UG - Apr 19, 01:50 UTCApr 19, 02:00 UTC10m
2026-04-19 N911UG - Apr 19, 00:35 UTCApr 19, 00:55 UTC20m
2026-04-18 N911UG - Apr 18, 23:10 UTCApr 18, 23:45 UTC35m
2026-04-17 N911UG - Apr 17, 17:45 UTCApr 17, 19:20 UTC1h 35m

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 N911UG page for operator, model, and routing details .

Mode-S AC9C2B frequently asked

What is Mode-S code AC9C2B?
AC9C2B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N911UG.
Where is Mode-S AC9C2B registered?
Mode-S code AC9C2B 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 AC9C2B broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC9C2B, octal 53116053, decimal 11,312,171.
What flights does AC9C2B operate?
Mode-S AC9C2B has broadcast 1 distinct callsign, including N911UG.