Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A523C6

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N430GT · BOEING 747-400 · operated by ATLAS AIR INC

Hex
A523C6
Octal
51221706
Decimal
10,822,598
Country
US
Tail
N430GT
Type
B744
No current signal · last broadcast 3h ago
Flights observed
187
Distinct callsigns
14
Country
US
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S A523C6.

Country allocation

The ICAO 24-bit address A523C6 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 14 distinct

Callsign Airline Flights Last seen
GTI8603 - 88 2026-07-07
GTI8602 - 62 2026-07-06
GTI8977 - 13 2026-06-27
GTI8976 - 10 2026-06-26
GTI8237 - 3 2026-07-13
GTI8439 Atlas Air 2 2026-05-06
GTI812 Atlas Air 2 2026-05-08
GTI9377 Atlas Air 1 2026-05-06
GTI9031 Atlas Air 1 2026-05-01
GTI8601 - 1 2026-07-07
GTI8238 - 1 2026-07-13
GTI8192 - 1 2026-07-14
GTI072 - 1 2026-07-08
GTI071 - 1 2026-07-08

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 GTI8192 - Jul 14, 05:25 UTCJul 14, 07:20 UTC1h 55m
2026-07-13 GTI8238 FRA → ORD Jul 13, 17:40 UTCJul 14, 01:55 UTC8h 15m
2026-07-13 GTI8237 - Jul 13, 13:35 UTCJul 13, 14:05 UTC30m
2026-07-13 GTI8237 - Jul 13, 06:05 UTCJul 13, 13:30 UTC7h 25m
2026-07-12 GTI8237 - Jul 12, 23:50 UTCJul 13, 02:45 UTC2h 55m
2026-07-08 GTI072 - Jul 8, 18:10 UTCJul 8, 18:40 UTC30m
2026-07-08 GTI071 - Jul 8, 09:10 UTCJul 8, 10:45 UTC1h 35m
2026-07-07 GTI8601 JFK → MIA Jul 7, 16:30 UTCJul 7, 18:50 UTC2h 20m
2026-07-07 GTI8603 ANC → JFK Jul 7, 08:05 UTCJul 7, 14:10 UTC6h 5m
2026-07-06 GTI8603 - Jul 6, 15:05 UTCJul 7, 05:50 UTC14h 45m
2026-07-06 GTI8603 - Jul 6, 09:35 UTCJul 7, 05:50 UTC20h 15m
2026-07-06 GTI8602 - Jul 6, 08:55 UTCJul 7, 05:50 UTC20h 55m
2026-07-06 GTI8602 JFK → ANC Jul 6, 00:00 UTCJul 6, 06:35 UTC6h 35m
2026-07-05 GTI8603 - Jul 5, 09:10 UTCJul 5, 15:35 UTC6h 25m
2026-07-04 GTI8603 - Jul 4, 11:50 UTCJul 5, 07:05 UTC19h 15m
2026-07-04 GTI8603 ANC → ANC Jul 4, 10:40 UTCJul 5, 07:05 UTC20h 25m
2026-07-04 GTI8602 JFK → ANC Jul 4, 01:25 UTCJul 4, 08:10 UTC6h 45m
2026-07-02 GTI8603 ANC → JFK Jul 2, 12:00 UTCJul 2, 18:25 UTC6h 25m
2026-07-01 GTI8603 - Jul 1, 17:10 UTCJul 2, 08:40 UTC15h 30m
2026-07-01 GTI8603 - Jul 1, 11:35 UTCJul 2, 08:40 UTC21h 5m
2026-07-01 GTI8603 ANC → ANC Jul 1, 11:05 UTCJul 2, 08:40 UTC21h 35m
2026-07-01 GTI8602 - Jul 1, 02:10 UTCJul 1, 08:50 UTC6h 40m
2026-06-30 GTI8603 ANC → JFK Jun 30, 13:45 UTCJun 30, 20:30 UTC6h 45m
2026-06-29 GTI8603 - Jun 29, 20:24 UTCJun 30, 11:40 UTC15h 16m
2026-06-29 GTI8603 - Jun 29, 15:45 UTCJun 30, 11:40 UTC19h 56m
2026-06-29 GTI8602 - Jun 29, 14:29 UTCJun 30, 11:40 UTC21h 11m
2026-06-29 GTI8602 - Jun 29, 04:45 UTCJun 29, 11:29 UTC6h 45m
2026-06-27 GTI8977 - Jun 27, 10:10 UTCJun 27, 16:20 UTC6h 10m
2026-06-27 GTI8977 - Jun 27, 00:34 UTCJun 27, 07:55 UTC7h 20m
2026-06-26 GTI8976 - Jun 26, 08:30 UTCJun 26, 16:54 UTC8h 25m
2026-06-25 GTI8976 - Jun 25, 23:30 UTCJun 26, 06:04 UTC6h 35m
2026-06-25 GTI8603 ANC → JFK Jun 25, 11:50 UTCJun 25, 18:19 UTC6h 30m
2026-06-24 GTI8603 - Jun 24, 16:54 UTCJun 25, 09:40 UTC16h 45m
2026-06-24 GTI8603 - Jun 24, 11:34 UTCJun 25, 09:40 UTC22h 5m
2026-06-24 GTI8602 - Jun 24, 10:49 UTCJun 25, 09:29 UTC22h 40m
2026-06-24 GTI8602 JFK → ANC Jun 24, 02:05 UTCJun 24, 08:35 UTC6h 30m
2026-06-23 GTI8603 - Jun 23, 11:10 UTCJun 23, 17:39 UTC6h 30m
2026-06-22 GTI8603 - Jun 22, 16:54 UTCJun 23, 08:50 UTC15h 55m
2026-06-22 GTI8603 - Jun 22, 11:35 UTCJun 23, 08:50 UTC21h 15m
2026-06-22 GTI8603 ANC → ANC Jun 22, 11:00 UTCJun 23, 08:50 UTC21h 50m
2026-06-22 GTI8602 JFK → ANC Jun 22, 02:40 UTCJun 22, 09:19 UTC6h 40m
2026-06-20 GTI8977 ANC → JFK Jun 20, 16:55 UTCJun 20, 23:14 UTC6h 20m
2026-06-19 GTI8977 - Jun 19, 19:49 UTCJun 20, 14:29 UTC18h 40m
2026-06-19 GTI8976 - Jun 19, 14:19 UTCJun 20, 13:29 UTC23h 10m
2026-06-19 GTI8976 JFK → ANC Jun 19, 05:24 UTCJun 19, 11:49 UTC6h 25m
2026-06-18 GTI8977 ANC → JFK Jun 18, 09:55 UTCJun 18, 16:25 UTC6h 30m
2026-06-17 GTI8977 - Jun 17, 13:50 UTCJun 18, 07:15 UTC17h 25m
2026-06-17 GTI8977 - Jun 17, 09:35 UTCJun 18, 07:15 UTC21h 40m
2026-06-17 GTI8976 - Jun 17, 07:55 UTCJun 18, 07:15 UTC23h 20m
2026-06-16 GTI8976 - Jun 16, 23:05 UTCJun 17, 05:35 UTC6h 30m

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 N430GT page for operator, model, and routing details .

Mode-S A523C6 frequently asked

What is Mode-S code A523C6?
A523C6 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N430GT.
Where is Mode-S A523C6 registered?
Mode-S code A523C6 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 A523C6 broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A523C6, octal 51221706, decimal 10,822,598.
What flights does A523C6 operate?
Mode-S A523C6 has broadcast 14 distinct callsigns, including GTI8603, GTI8602, GTI8977, GTI8976, GTI8237.