sensors Mode-S transponder

AC956B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N91MF · BEECH 200 Super King Air · operated by CKW AVIATION LLC

Hex
AC956B
Octal
53112553
Decimal
11,310,443
Country
US
Tail
N91MF
Type
BE20
No current signal · last broadcast 15h ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S AC956B.

Country allocation

The ICAO 24-bit address AC956B 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
N91MF - 11 2026-04-18

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-18 N91MF - Apr 18, 02:10 UTCApr 18, 02:35 UTC25m
2026-04-17 N91MF - Apr 17, 22:50 UTCApr 17, 23:20 UTC30m
2026-04-17 N91MF - Apr 17, 21:25 UTCApr 17, 21:35 UTC10m
2026-04-17 N91MF - Apr 17, 19:25 UTCApr 17, 21:20 UTC1h 55m
2026-04-17 N91MF - Apr 17, 18:05 UTCApr 17, 19:20 UTC1h 15m
2026-04-17 N91MF - Apr 17, 15:20 UTCApr 17, 17:15 UTC1h 55m
2026-04-17 N91MF - Apr 17, 14:45 UTCApr 17, 15:15 UTC29m
2026-04-13 N91MF - Apr 13, 19:50 UTCApr 13, 20:00 UTC10m
2026-04-13 N91MF - Apr 13, 16:50 UTCApr 13, 20:00 UTC3h 10m
2026-04-13 N91MF - Apr 13, 15:50 UTCApr 13, 16:00 UTC10m
2026-04-13 N91MF - Apr 13, 13:20 UTCApr 13, 16:00 UTC2h 40m

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 N91MF page for operator, model, and routing details .

Mode-S AC956B frequently asked

What is Mode-S code AC956B?
AC956B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N91MF.
Where is Mode-S AC956B registered?
Mode-S code AC956B 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 AC956B broadcasting right now?
No active broadcast right now. Last signal was 15h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC956B, octal 53112553, decimal 11,310,443.
What flights does AC956B operate?
Mode-S AC956B has broadcast 1 distinct callsign, including N91MF.