sensors Mode-S transponder

A9021C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N68NT · BEECH 90 King Air · operated by UNION AIR LLC

Hex
A9021C
Octal
52201034
Decimal
11,076,124
Country
US
Tail
N68NT
Type
BE9L
No current signal · last broadcast Jul 26, 20:30 UTC
Flights observed
28
Distinct callsigns
1
Country
US
Last broadcast
Jul 26, 20:30 UTC

Last known position

Most recent position reported by Mode-S A9021C.

Country allocation

The ICAO 24-bit address A9021C 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
N68NT - 28 2026-07-26

Recent flights last 28

DateFlightRouteTakeoffLandingDuration
2026-07-26 N68NT - Jul 26, 20:05 UTCJul 26, 20:30 UTC25m
2026-07-25 N68NT - Jul 25, 00:10 UTCJul 25, 00:35 UTC25m
2026-07-23 N68NT - Jul 23, 22:25 UTCJul 23, 23:00 UTC35m
2026-07-23 N68NT - Jul 23, 02:15 UTCJul 23, 02:35 UTC20m
2026-07-22 N68NT - Jul 22, 21:50 UTCJul 22, 22:20 UTC30m
2026-07-20 N68NT - Jul 20, 18:05 UTCJul 20, 18:20 UTC15m
2026-07-20 N68NT - Jul 20, 15:30 UTCJul 20, 15:50 UTC20m
2026-07-20 N68NT - Jul 20, 01:55 UTCJul 20, 02:20 UTC25m
2026-07-18 N68NT - Jul 18, 20:50 UTCJul 18, 21:05 UTC15m
2026-07-18 N68NT - Jul 18, 18:10 UTCJul 18, 18:30 UTC20m
2026-07-16 N68NT - Jul 16, 22:49 UTCJul 16, 23:15 UTC25m
2026-07-16 N68NT - Jul 16, 19:35 UTCJul 16, 20:05 UTC30m
2026-07-11 N68NT - Jul 11, 14:25 UTCJul 11, 15:20 UTC55m
2026-07-10 N68NT - Jul 10, 16:10 UTCJul 10, 17:15 UTC1h 5m
2026-07-09 N68NT - Jul 9, 02:40 UTCJul 9, 03:05 UTC25m
2026-07-08 N68NT - Jul 8, 23:55 UTCJul 9, 00:25 UTC30m
2026-06-20 N68NT - Jun 20, 00:09 UTCJun 20, 02:00 UTC1h 50m
2026-06-17 N68NT - Jun 17, 21:35 UTCJun 17, 23:10 UTC1h 35m
2026-06-15 N68NT - Jun 15, 18:25 UTCJun 15, 18:40 UTC15m
2026-06-15 N68NT - Jun 15, 15:45 UTCJun 15, 15:55 UTC10m
2026-06-10 N68NT - Jun 10, 01:00 UTCJun 10, 01:25 UTC25m
2026-06-09 N68NT - Jun 9, 21:50 UTCJun 9, 22:15 UTC25m
2026-06-09 N68NT - Jun 9, 00:05 UTCJun 9, 00:25 UTC20m
2026-06-08 N68NT - Jun 8, 22:15 UTCJun 8, 22:45 UTC30m
2026-06-07 N68NT - Jun 7, 19:35 UTCJun 7, 21:25 UTC1h 50m
2026-06-05 N68NT - Jun 5, 17:35 UTCJun 5, 19:15 UTC1h 40m
2026-05-03 N68NT - May 3, 00:01 UTCMay 3, 00:20 UTC20m
2026-05-02 N68NT - May 2, 18:40 UTCMay 2, 19:10 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 N68NT page for operator, model, and routing details .

Mode-S A9021C frequently asked

What is Mode-S code A9021C?
A9021C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N68NT.
Where is Mode-S A9021C registered?
Mode-S code A9021C 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 A9021C broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 20:30 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9021C, octal 52201034, decimal 11,076,124.
What flights does A9021C operate?
Mode-S A9021C has broadcast 1 distinct callsign, including N68NT.