sensors Mode-S transponder

AACA81

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N7949N · PIPER PA-28-140/150/160/180 · operated by GUESS-SLATOSKY CARRIE, SLATOSKY JOHN JAMES JR

Hex
AACA81
Octal
52545201
Decimal
11,192,961
Country
US
Tail
N7949N
Type
P28A
No current signal · last broadcast 14d ago
Flights observed
11
Distinct callsigns
1
Country
US
Last broadcast
14d ago

Last known position

Most recent position reported by Mode-S AACA81.

Country allocation

The ICAO 24-bit address AACA81 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
N7949N - 11 2026-07-21

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-07-21 N7949N - Jul 21, 12:55 UTCJul 21, 14:00 UTC1h 5m
2026-06-20 N7949N - Jun 20, 18:54 UTCJun 20, 19:09 UTC15m
2026-06-20 N7949N - Jun 20, 16:29 UTCJun 20, 16:44 UTC15m
2026-06-13 N7949N - Jun 13, 14:05 UTCJun 13, 14:15 UTC10m
2026-06-13 N7949N - Jun 13, 12:40 UTCJun 13, 12:55 UTC15m
2026-05-16 N7949N - May 16, 21:15 UTCMay 16, 21:45 UTC30m
2026-05-16 N7949N - May 16, 14:11 UTCMay 16, 14:41 UTC30m
2026-04-24 N7949N - Apr 24, 17:30 UTCApr 24, 18:05 UTC35m
2026-04-24 N7949N - Apr 24, 14:50 UTCApr 24, 15:10 UTC20m
2026-04-15 N7949N - Apr 15, 17:05 UTCApr 15, 17:20 UTC15m
2026-04-15 N7949N - Apr 15, 13:50 UTCApr 15, 14:55 UTC1h 4m

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 N7949N page for operator, model, and routing details .

Mode-S AACA81 frequently asked

What is Mode-S code AACA81?
AACA81 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N7949N.
Where is Mode-S AACA81 registered?
Mode-S code AACA81 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 AACA81 broadcasting right now?
No active broadcast right now. Last signal was 14d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AACA81, octal 52545201, decimal 11,192,961.
What flights does AACA81 operate?
Mode-S AACA81 has broadcast 1 distinct callsign, including N7949N.