sensors Mode-S transponder

A3F6D8

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N3546E · CESSNA 172 Skyhawk · operated by DUSSINGER ANDREW M

Hex
A3F6D8
Octal
50773330
Decimal
10,745,560
Country
US
Tail
N3546E
Type
C172
No current signal · last broadcast 19h ago
Flights observed
8
Distinct callsigns
1
Country
US
Last broadcast
19h ago

Last known position

Most recent position reported by Mode-S A3F6D8.

Country allocation

The ICAO 24-bit address A3F6D8 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
N3546E - 8 2026-05-29

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-05-29 N3546E - May 29, 14:25 UTCMay 29, 14:40 UTC15m
2026-05-29 N3546E - May 29, 13:10 UTCMay 29, 13:30 UTC20m
2026-05-27 N3546E - May 27, 22:10 UTCMay 28, 00:20 UTC2h 10m
2026-05-27 N3546E HAR → HVN May 27, 15:05 UTCMay 27, 17:15 UTC2h 10m
2026-05-20 N3546E - May 20, 14:35 UTCMay 20, 15:05 UTC30m
2026-05-20 N3546E - May 20, 12:30 UTCMay 20, 13:10 UTC40m
2026-05-12 N3546E - May 12, 13:35 UTCMay 12, 13:45 UTC10m
2026-05-01 N3546E HAR → HAR May 1, 14:30 UTCMay 1, 15:20 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 N3546E page for operator, model, and routing details .

Mode-S A3F6D8 frequently asked

What is Mode-S code A3F6D8?
A3F6D8 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N3546E.
Where is Mode-S A3F6D8 registered?
Mode-S code A3F6D8 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 A3F6D8 broadcasting right now?
No active broadcast right now. Last signal was 19h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A3F6D8, octal 50773330, decimal 10,745,560.
What flights does A3F6D8 operate?
Mode-S A3F6D8 has broadcast 1 distinct callsign, including N3546E.