sensors Mode-S transponder

A91CFF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N6868P · PILATUS PC-12 · operated by ARCOLA LEASING LLC

Hex
A91CFF
Octal
52216377
Decimal
11,083,007
Country
US
Tail
N6868P
Type
PC12
No current signal · last broadcast 1d ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A91CFF.

Country allocation

The ICAO 24-bit address A91CFF 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
N6868P - 1 2026-04-13

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-13 N6868P - Apr 13, 13:50 UTCApr 13, 14:40 UTC50m

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 N6868P page for operator, model, and routing details .

Mode-S A91CFF frequently asked

What is Mode-S code A91CFF?
A91CFF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N6868P.
Where is Mode-S A91CFF registered?
Mode-S code A91CFF 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 A91CFF broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A91CFF, octal 52216377, decimal 11,083,007.
What flights does A91CFF operate?
Mode-S A91CFF has broadcast 1 distinct callsign, including N6868P.