sensors Mode-S transponder

A63DE2

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N501CJ · CESSNA 525A Citation CJ2 · operated by OSTRICH BOOT LLC

Hex
A63DE2
Octal
51436742
Decimal
10,894,818
Country
US
Tail
N501CJ
Type
C25A
No current signal · last broadcast 4d ago
Flights observed
20
Distinct callsigns
1
Country
US
Last broadcast
4d ago

Last known position

Most recent position reported by Mode-S A63DE2.

Country allocation

The ICAO 24-bit address A63DE2 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
N501CJ - 20 2026-05-22

Recent flights last 20

DateFlightRouteTakeoffLandingDuration
2026-05-22 N501CJ - May 22, 14:55 UTCMay 22, 16:50 UTC1h 55m
2026-05-22 N501CJ - May 22, 12:45 UTCMay 22, 13:40 UTC55m
2026-05-17 N501CJ - May 17, 23:00 UTCMay 18, 00:25 UTC1h 25m
2026-05-17 N501CJ - May 17, 20:25 UTCMay 17, 21:35 UTC1h 10m
2026-05-14 N501CJ - May 14, 20:25 UTCMay 14, 21:40 UTC1h 15m
2026-05-14 N501CJ - May 14, 18:20 UTCMay 14, 19:45 UTC1h 25m
2026-05-14 N501CJ - May 14, 02:30 UTCMay 14, 02:50 UTC20m
2026-05-13 N501CJ - May 13, 19:55 UTCMay 13, 20:20 UTC25m
2026-05-12 N501CJ - May 12, 19:55 UTCMay 12, 21:10 UTC1h 15m
2026-05-12 N501CJ - May 12, 17:25 UTCMay 12, 18:45 UTC1h 20m
2026-05-09 N501CJ - May 9, 16:55 UTCMay 9, 17:35 UTC40m
2026-05-09 N501CJ - May 9, 15:15 UTCMay 9, 16:10 UTC55m
2026-05-01 N501CJ - May 1, 21:25 UTCMay 1, 22:40 UTC1h 15m
2026-05-01 N501CJ - May 1, 19:30 UTCMay 1, 20:35 UTC1h 5m
2026-05-01 N501CJ - May 1, 19:00 UTCMay 1, 19:25 UTC25m
2026-04-30 N501CJ - Apr 30, 21:20 UTCApr 30, 22:20 UTC1h 0m
2026-04-30 N501CJ - Apr 30, 13:15 UTCApr 30, 14:25 UTC1h 10m
2026-04-30 N501CJ - Apr 30, 01:30 UTCApr 30, 02:00 UTC30m
2026-04-29 N501CJ - Apr 29, 22:40 UTCApr 29, 23:50 UTC1h 9m
2026-04-29 N501CJ - Apr 29, 20:35 UTCApr 29, 21:45 UTC1h 10m

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 N501CJ page for operator, model, and routing details .

Mode-S A63DE2 frequently asked

What is Mode-S code A63DE2?
A63DE2 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N501CJ.
Where is Mode-S A63DE2 registered?
Mode-S code A63DE2 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 A63DE2 broadcasting right now?
No active broadcast right now. Last signal was 4d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A63DE2, octal 51436742, decimal 10,894,818.
What flights does A63DE2 operate?
Mode-S A63DE2 has broadcast 1 distinct callsign, including N501CJ.