sensors Mode-S transponder

A4AC66

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N40XS · BEECH 36 Bonanza · operated by SASSER F MICHAEL

Hex
A4AC66
Octal
51126146
Decimal
10,792,038
Country
US
Tail
N40XS
Type
BE36
No current signal · last broadcast 7h ago
Flights observed
13
Distinct callsigns
1
Country
US
Last broadcast
7h ago

Last known position

Most recent position reported by Mode-S A4AC66.

Country allocation

The ICAO 24-bit address A4AC66 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
N40XS - 13 2026-07-06

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-07-06 N40XS - Jul 6, 22:10 UTCJul 6, 22:30 UTC20m
2026-06-17 N40XS - Jun 17, 16:35 UTCJun 17, 16:55 UTC20m
2026-06-05 N40XS - Jun 5, 17:20 UTCJun 5, 18:20 UTC1h 0m
2026-05-31 N40XS - May 31, 21:00 UTCMay 31, 22:05 UTC1h 5m
2026-05-28 N40XS - May 28, 17:20 UTCMay 28, 18:50 UTC1h 30m
2026-05-28 N40XS - May 28, 12:50 UTCMay 28, 14:15 UTC1h 25m
2026-05-25 N40XS - May 25, 23:00 UTCMay 26, 00:09 UTC1h 10m
2026-05-22 N40XS - May 22, 15:15 UTCMay 22, 16:20 UTC1h 5m
2026-05-21 N40XS - May 21, 18:55 UTCMay 21, 19:30 UTC35m
2026-05-21 N40XS - May 21, 17:15 UTCMay 21, 18:25 UTC1h 10m
2026-05-17 N40XS - May 17, 15:35 UTCMay 17, 17:50 UTC2h 15m
2026-05-13 N40XS - May 13, 15:10 UTCMay 13, 15:55 UTC45m
2026-05-13 N40XS - May 13, 13:45 UTCMay 13, 14:35 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 N40XS page for operator, model, and routing details .

Mode-S A4AC66 frequently asked

What is Mode-S code A4AC66?
A4AC66 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N40XS.
Where is Mode-S A4AC66 registered?
Mode-S code A4AC66 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 A4AC66 broadcasting right now?
No active broadcast right now. Last signal was 7h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4AC66, octal 51126146, decimal 10,792,038.
What flights does A4AC66 operate?
Mode-S A4AC66 has broadcast 1 distinct callsign, including N40XS.