sensors Mode-S transponder

A3C989

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N343MC · operated by CHILDS JEFFREY A

Hex
A3C989
Octal
50744611
Decimal
10,733,961
Country
US
Tail
N343MC
No current signal · last broadcast Jul 25, 20:20 UTC
Flights observed
27
Distinct callsigns
1
Country
US
Last broadcast
Jul 25, 20:20 UTC

Last known position

Most recent position reported by Mode-S A3C989.

Country allocation

The ICAO 24-bit address A3C989 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
N343MC - 27 2026-07-25

Recent flights last 27

DateFlightRouteTakeoffLandingDuration
2026-07-25 N343MC - Jul 25, 19:50 UTCJul 25, 20:20 UTC30m
2026-07-25 N343MC - Jul 25, 17:40 UTCJul 25, 18:50 UTC1h 10m
2026-07-23 N343MC - Jul 23, 17:25 UTCJul 23, 19:25 UTC2h 0m
2026-07-23 N343MC - Jul 23, 13:45 UTCJul 23, 15:40 UTC1h 55m
2026-07-19 N343MC - Jul 19, 22:45 UTCJul 19, 22:55 UTC10m
2026-07-19 N343MC - Jul 19, 21:30 UTCJul 19, 21:45 UTC15m
2026-07-19 N343MC - Jul 19, 19:30 UTCJul 19, 20:30 UTC1h 0m
2026-07-19 N343MC - Jul 19, 16:55 UTCJul 19, 18:20 UTC1h 25m
2026-07-19 N343MC - Jul 19, 11:30 UTCJul 19, 14:35 UTC3h 5m
2026-07-17 N343MC - Jul 17, 18:19 UTCJul 17, 19:25 UTC1h 5m
2026-07-15 N343MC - Jul 15, 15:40 UTCJul 15, 15:50 UTC10m
2026-07-04 N343MC RKH → RKH Jul 4, 14:20 UTCJul 4, 15:00 UTC40m
2026-06-20 N343MC RKH → RKH Jun 20, 13:24 UTCJun 20, 14:50 UTC1h 25m
2026-06-17 N343MC - Jun 17, 15:15 UTCJun 17, 15:25 UTC10m
2026-06-06 N343MC - Jun 6, 15:44 UTCJun 6, 15:54 UTC10m
2026-06-06 N343MC - Jun 6, 13:34 UTCJun 6, 14:00 UTC25m
2026-06-05 N343MC - Jun 5, 14:45 UTCJun 5, 15:30 UTC45m
2026-06-03 N343MC - Jun 3, 19:05 UTCJun 3, 19:45 UTC40m
2026-06-03 N343MC - Jun 3, 15:15 UTCJun 3, 15:35 UTC20m
2026-05-27 N343MC - May 27, 21:40 UTCMay 27, 22:25 UTC45m
2026-05-18 N343MC - May 18, 14:00 UTCMay 18, 14:45 UTC45m
2026-05-16 N343MC - May 16, 16:25 UTCMay 16, 16:55 UTC30m
2026-05-15 N343MC - May 15, 18:40 UTCMay 15, 19:20 UTC40m
2026-05-15 N343MC - May 15, 16:10 UTCMay 15, 16:50 UTC40m
2026-05-12 N343MC - May 12, 13:40 UTCMay 12, 15:30 UTC1h 50m
2026-05-11 N343MC - May 11, 22:05 UTCMay 11, 22:35 UTC29m
2026-05-11 N343MC - May 11, 21:15 UTCMay 11, 21:30 UTC15m

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 N343MC page for operator, model, and routing details .

Mode-S A3C989 frequently asked

What is Mode-S code A3C989?
A3C989 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N343MC.
Where is Mode-S A3C989 registered?
Mode-S code A3C989 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 A3C989 broadcasting right now?
No active broadcast right now. Last signal was Jul 25, 20:20 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A3C989, octal 50744611, decimal 10,733,961.
What flights does A3C989 operate?
Mode-S A3C989 has broadcast 1 distinct callsign, including N343MC.