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sensors Mode-S transponder

A6B439

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N531AW · BEECH 300 Super King Air · operated by CSI 135 DIVISION LLC

Hex
A6B439
Octal
51532071
Decimal
10,925,113
Country
US
Tail
N531AW
Type
BE30
No current signal · last broadcast Jul 26, 22:10 UTC
Flights observed
284
Distinct callsigns
1
Country
US
Last broadcast
Jul 26, 22:10 UTC

Last known position

Most recent position reported by Mode-S A6B439.

Country allocation

The ICAO 24-bit address A6B439 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
CSI531 - 284 2026-07-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 CSI531 - Jul 26, 20:45 UTCJul 26, 22:10 UTC1h 25m
2026-07-26 CSI531 - Jul 26, 17:20 UTCJul 26, 17:55 UTC35m
2026-07-26 CSI531 - Jul 26, 16:00 UTCJul 26, 16:20 UTC20m
2026-07-25 CSI531 - Jul 25, 02:15 UTCJul 25, 03:45 UTC1h 30m
2026-07-24 CSI531 - Jul 24, 22:30 UTCJul 24, 23:10 UTC40m
2026-07-24 CSI531 - Jul 24, 16:45 UTCJul 24, 17:10 UTC25m
2026-07-24 CSI531 - Jul 24, 03:20 UTCJul 24, 03:40 UTC20m
2026-07-24 CSI531 - Jul 24, 01:15 UTCJul 24, 01:45 UTC30m
2026-07-23 CSI531 - Jul 23, 23:45 UTCJul 24, 00:00 UTC15m
2026-07-23 CSI531 - Jul 23, 19:50 UTCJul 23, 20:25 UTC35m
2026-07-23 CSI531 - Jul 23, 17:25 UTCJul 23, 17:50 UTC25m
2026-07-23 CSI531 - Jul 23, 04:45 UTCJul 23, 05:00 UTC15m
2026-07-23 CSI531 - Jul 23, 02:10 UTCJul 23, 03:00 UTC50m
2026-07-22 CSI531 - Jul 22, 22:25 UTCJul 22, 22:55 UTC30m
2026-07-22 CSI531 - Jul 22, 17:05 UTCJul 22, 17:35 UTC30m
2026-07-22 CSI531 - Jul 22, 00:25 UTCJul 22, 00:40 UTC15m
2026-07-21 CSI531 - Jul 21, 19:35 UTCJul 21, 20:10 UTC35m
2026-07-21 CSI531 - Jul 21, 18:30 UTCJul 21, 18:55 UTC25m
2026-07-21 CSI531 - Jul 21, 16:55 UTCJul 21, 17:15 UTC20m
2026-07-20 CSI531 - Jul 20, 03:00 UTCJul 20, 03:15 UTC15m
2026-07-20 CSI531 - Jul 20, 00:15 UTCJul 20, 00:40 UTC25m
2026-07-19 CSI531 - Jul 19, 16:55 UTCJul 19, 17:20 UTC25m
2026-07-19 CSI531 - Jul 19, 00:25 UTCJul 19, 00:55 UTC30m
2026-07-18 CSI531 - Jul 18, 21:40 UTCJul 18, 22:30 UTC50m
2026-07-18 CSI531 - Jul 18, 20:50 UTCJul 18, 21:10 UTC20m
2026-07-18 CSI531 - Jul 18, 06:45 UTCJul 18, 07:10 UTC25m
2026-07-18 CSI531 - Jul 18, 05:15 UTCJul 18, 05:40 UTC25m
2026-07-18 CSI531 - Jul 18, 00:15 UTCJul 18, 00:45 UTC30m
2026-07-17 CSI531 - Jul 17, 22:49 UTCJul 17, 23:20 UTC30m
2026-07-17 CSI531 - Jul 17, 20:29 UTCJul 17, 20:40 UTC10m
2026-07-17 CSI531 - Jul 17, 19:05 UTCJul 17, 19:15 UTC10m
2026-07-17 CSI531 - Jul 17, 16:44 UTCJul 17, 17:15 UTC30m
2026-07-17 CSI531 - Jul 17, 14:55 UTCJul 17, 15:15 UTC20m
2026-07-17 CSI531 - Jul 17, 04:54 UTCJul 17, 05:25 UTC30m
2026-07-17 CSI531 - Jul 17, 02:54 UTCJul 17, 03:25 UTC30m
2026-07-16 CSI531 - Jul 16, 23:55 UTCJul 17, 00:25 UTC30m
2026-07-16 CSI531 - Jul 16, 21:10 UTCJul 16, 22:00 UTC50m
2026-07-16 CSI531 - Jul 16, 18:19 UTCJul 16, 18:44 UTC25m
2026-07-16 CSI531 - Jul 16, 16:09 UTCJul 16, 16:30 UTC20m
2026-07-16 CSI531 - Jul 16, 14:50 UTCJul 16, 15:10 UTC20m
2026-07-16 CSI531 - Jul 16, 01:55 UTCJul 16, 02:25 UTC30m
2026-07-15 CSI531 - Jul 15, 22:15 UTCJul 15, 22:55 UTC40m
2026-07-15 CSI531 - Jul 15, 19:30 UTCJul 15, 20:05 UTC35m
2026-07-15 CSI531 - Jul 15, 17:05 UTCJul 15, 17:30 UTC25m
2026-07-15 CSI531 - Jul 15, 10:15 UTCJul 15, 10:35 UTC20m
2026-07-15 CSI531 - Jul 15, 07:35 UTCJul 15, 08:35 UTC1h 0m
2026-07-15 CSI531 - Jul 15, 04:30 UTCJul 15, 05:20 UTC50m
2026-07-15 CSI531 - Jul 15, 01:00 UTCJul 15, 01:15 UTC15m
2026-07-14 CSI531 - Jul 14, 05:30 UTCJul 14, 06:05 UTC35m
2026-07-14 CSI531 - Jul 14, 03:35 UTCJul 14, 04:05 UTC30m

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 N531AW page for operator, model, and routing details .

Mode-S A6B439 frequently asked

What is Mode-S code A6B439?
A6B439 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N531AW.
Where is Mode-S A6B439 registered?
Mode-S code A6B439 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 A6B439 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:10 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A6B439, octal 51532071, decimal 10,925,113.
What flights does A6B439 operate?
Mode-S A6B439 has broadcast 1 distinct callsign, including CSI531.