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sensors Mode-S transponder

A75A21

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N573FX · BOMBARDIER BD-100 Challenger 350 · operated by FLEXJET LLC, STOLTZ REALTY OF DELAWARE INC, C & T PARTNERS LLC, MILGARD JIM SR, NAUSET AVIATION LLC, NEWCO DISTRIBUTORS INC

Hex
A75A21
Octal
51655041
Decimal
10,967,585
Country
US
Tail
N573FX
Type
CL35
Broadcasting now · callsign LXJ573 · 18,025 ft
Flights observed
258
Distinct callsigns
1
Country
US
Last broadcast
Jul 26, 22:15 UTC

Current position

A75A21 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A75A21 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
LXJ573 - 258 2026-07-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 LXJ573 - Jul 26, 20:15 UTCJul 26, 22:15 UTC2h 0m
2026-07-26 LXJ573 - Jul 26, 16:40 UTCJul 26, 19:15 UTC2h 35m
2026-07-26 LXJ573 - Jul 26, 13:55 UTCJul 26, 14:35 UTC40m
2026-07-26 LXJ573 - Jul 26, 12:25 UTCJul 26, 12:55 UTC30m
2026-07-25 LXJ573 - Jul 25, 17:55 UTCJul 25, 19:05 UTC1h 10m
2026-07-25 LXJ573 - Jul 25, 14:30 UTCJul 25, 15:50 UTC1h 20m
2026-07-24 LXJ573 CAK → IND Jul 24, 20:15 UTCJul 24, 21:05 UTC50m
2026-07-24 LXJ573 LUK → CAK Jul 24, 17:45 UTCJul 24, 18:20 UTC35m
2026-07-24 LXJ573 - Jul 24, 14:10 UTCJul 24, 16:15 UTC2h 5m
2026-07-23 LXJ573 - Jul 23, 19:15 UTCJul 23, 20:50 UTC1h 35m
2026-07-23 LXJ573 - Jul 23, 17:10 UTCJul 23, 18:20 UTC1h 10m
2026-07-23 LXJ573 - Jul 23, 14:50 UTCJul 23, 15:20 UTC30m
2026-07-23 LXJ573 - Jul 23, 12:20 UTCJul 23, 12:50 UTC30m
2026-07-22 LXJ573 - Jul 22, 19:40 UTCJul 22, 21:30 UTC1h 50m
2026-07-22 LXJ573 - Jul 22, 15:55 UTCJul 22, 16:40 UTC45m
2026-07-22 LXJ573 MDW → PTK Jul 22, 13:05 UTCJul 22, 13:45 UTC40m
2026-07-21 LXJ573 - Jul 21, 17:20 UTCJul 21, 20:00 UTC2h 40m
2026-07-21 LXJ573 - Jul 21, 15:35 UTCJul 21, 16:00 UTC25m
2026-07-21 LXJ573 - Jul 21, 12:10 UTCJul 21, 13:45 UTC1h 35m
2026-07-20 LXJ573 CMH → USA Jul 20, 21:35 UTCJul 20, 22:30 UTC55m
2026-07-20 LXJ573 - Jul 20, 20:00 UTCJul 20, 20:50 UTC50m
2026-07-20 LXJ573 - Jul 20, 17:15 UTCJul 20, 18:45 UTC1h 30m
2026-07-20 LXJ573 - Jul 20, 13:20 UTCJul 20, 16:10 UTC2h 50m
2026-07-19 LXJ573 - Jul 19, 23:10 UTCJul 19, 23:45 UTC35m
2026-07-19 LXJ573 - Jul 19, 04:50 UTCJul 19, 06:00 UTC1h 10m
2026-07-19 LXJ573 - Jul 19, 03:15 UTCJul 19, 03:45 UTC30m
2026-07-19 LXJ573 - Jul 19, 02:00 UTCJul 19, 02:35 UTC35m
2026-07-19 LXJ573 - Jul 19, 00:00 UTCJul 19, 00:40 UTC40m
2026-07-18 LXJ573 - Jul 18, 20:15 UTCJul 18, 22:35 UTC2h 20m
2026-07-18 LXJ573 - Jul 18, 11:50 UTCJul 18, 19:00 UTC7h 10m
2026-07-17 LXJ573 SJC → DAL Jul 17, 22:25 UTCJul 18, 01:50 UTC3h 25m
2026-07-15 LXJ573 - Jul 15, 22:20 UTCJul 16, 03:20 UTC5h 0m
2026-07-14 LXJ573 - Jul 14, 22:50 UTCJul 15, 04:05 UTC5h 15m
2026-07-14 LXJ573 - Jul 14, 17:15 UTCJul 14, 21:50 UTC4h 35m
2026-07-13 LXJ573 - Jul 13, 23:55 UTCJul 14, 03:15 UTC3h 20m
2026-07-13 LXJ573 - Jul 13, 21:50 UTCJul 13, 22:20 UTC30m
2026-07-12 LXJ573 DEN → BNA Jul 12, 22:30 UTCJul 13, 00:45 UTC2h 15m
2026-07-12 LXJ573 LAS → DEN Jul 12, 19:25 UTCJul 12, 21:00 UTC1h 35m
2026-07-12 LXJ573 - Jul 12, 16:15 UTCJul 12, 17:25 UTC1h 10m
2026-07-11 LXJ573 - Jul 11, 20:55 UTCJul 11, 23:05 UTC2h 10m
2026-07-11 LXJ573 DAL → APA Jul 11, 15:30 UTCJul 11, 17:05 UTC1h 35m
2026-07-10 LXJ573 - Jul 10, 20:20 UTCJul 10, 23:25 UTC3h 5m
2026-07-10 LXJ573 - Jul 10, 13:30 UTCJul 10, 19:10 UTC5h 40m
2026-07-09 LXJ573 - Jul 9, 19:30 UTCJul 9, 20:40 UTC1h 10m
2026-07-09 LXJ573 - Jul 9, 17:05 UTCJul 9, 18:15 UTC1h 10m
2026-07-09 LXJ573 - Jul 9, 13:20 UTCJul 9, 14:20 UTC1h 0m
2026-07-09 LXJ573 - Jul 9, 11:25 UTCJul 9, 11:55 UTC30m
2026-07-08 LXJ573 - Jul 8, 21:30 UTCJul 8, 22:50 UTC1h 20m
2026-07-08 LXJ573 - Jul 8, 15:45 UTCJul 8, 16:40 UTC55m
2026-07-08 LXJ573 - Jul 8, 14:45 UTCJul 8, 15:10 UTC25m

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 N573FX page for operator, model, and routing details .

Mode-S A75A21 frequently asked

What is Mode-S code A75A21?
A75A21 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N573FX.
Where is Mode-S A75A21 registered?
Mode-S code A75A21 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 A75A21 broadcasting right now?
Yes. Mode-S A75A21 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A75A21, octal 51655041, decimal 10,967,585.
What flights does A75A21 operate?
Mode-S A75A21 has broadcast 1 distinct callsign, including LXJ573.