sensors Mode-S transponder

A6FFF3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N550FL · PIPER PA-28-140/150/160/180 · operated by KENNEDY ADAM B

Hex
A6FFF3
Octal
51577763
Decimal
10,944,499
Country
US
Tail
N550FL
Type
P28A
No current signal · last broadcast 7d ago
Flights observed
13
Distinct callsigns
1
Country
US
Last broadcast
7d ago

Last known position

Most recent position reported by Mode-S A6FFF3.

Country allocation

The ICAO 24-bit address A6FFF3 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
N550FL - 13 2026-07-11

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-07-11 N550FL - Jul 11, 13:20 UTCJul 11, 14:15 UTC55m
2026-07-01 N550FL - Jul 1, 12:05 UTCJul 1, 12:40 UTC35m
2026-06-22 N550FL - Jun 22, 13:29 UTCJun 22, 13:39 UTC10m
2026-06-07 N550FL - Jun 7, 14:50 UTCJun 7, 15:25 UTC35m
2026-05-30 N550FL - May 30, 14:00 UTCMay 30, 14:30 UTC30m
2026-05-30 N550FL - May 30, 12:50 UTCMay 30, 13:05 UTC15m
2026-05-26 N550FL - May 26, 13:29 UTCMay 26, 14:00 UTC30m
2026-05-10 N550FL - May 10, 15:19 UTCMay 10, 15:45 UTC25m
2026-05-10 N550FL - May 10, 14:09 UTCMay 10, 14:25 UTC15m
2026-05-03 N550FL - May 3, 18:50 UTCMay 3, 19:10 UTC20m
2026-05-03 N550FL - May 3, 15:50 UTCMay 3, 16:34 UTC45m
2026-04-25 N550FL - Apr 25, 18:30 UTCApr 25, 19:15 UTC45m
2026-04-18 N550FL - Apr 18, 21:05 UTCApr 18, 21:15 UTC10m

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 N550FL page for operator, model, and routing details .

Mode-S A6FFF3 frequently asked

What is Mode-S code A6FFF3?
A6FFF3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N550FL.
Where is Mode-S A6FFF3 registered?
Mode-S code A6FFF3 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 A6FFF3 broadcasting right now?
No active broadcast right now. Last signal was 7d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6FFF3, octal 51577763, decimal 10,944,499.
What flights does A6FFF3 operate?
Mode-S A6FFF3 has broadcast 1 distinct callsign, including N550FL.