sensors Mode-S transponder

A491AE

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N394AJ · GULFSTREAM 4 · operated by G4SP HOLDINGS LLC

Hex
A491AE
Octal
51110656
Decimal
10,785,198
Country
US
Tail
N394AJ
Type
GLF4
No current signal · last broadcast 5d ago
Flights observed
31
Distinct callsigns
1
Country
US
Last broadcast
5d ago

Last known position

Most recent position reported by Mode-S A491AE.

Country allocation

The ICAO 24-bit address A491AE 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
N394AJ - 31 2026-06-07

Recent flights last 31

DateFlightRouteTakeoffLandingDuration
2026-06-07 N394AJ - Jun 7, 22:05 UTCJun 8, 03:55 UTC5h 50m
2026-06-07 N394AJ - Jun 7, 12:25 UTCJun 7, 13:05 UTC40m
2026-06-07 N394AJ - Jun 7, 10:15 UTCJun 7, 10:50 UTC35m
2026-06-05 N394AJ BGR → FXE Jun 5, 20:45 UTCJun 5, 23:55 UTC3h 10m
2026-06-05 N394AJ BCN → BGR Jun 5, 11:05 UTCJun 5, 19:05 UTC8h 0m
2026-06-04 N394AJ PPM → BCN Jun 4, 05:40 UTCJun 4, 13:40 UTC8h 0m
2026-06-02 N394AJ - Jun 2, 02:35 UTCJun 2, 05:00 UTC2h 25m
2026-06-01 N394AJ - Jun 1, 16:55 UTCJun 2, 01:25 UTC8h 30m
2026-05-29 N394AJ TEB → NCE May 29, 00:15 UTCMay 29, 07:40 UTC7h 25m
2026-05-28 N394AJ - May 28, 21:00 UTCMay 28, 23:25 UTC2h 25m
2026-05-27 N394AJ - May 27, 23:50 UTCMay 28, 02:25 UTC2h 35m
2026-05-27 N394AJ IBZ → TEB May 27, 13:30 UTCMay 27, 21:30 UTC8h 0m
2026-05-25 N394AJ SVQ → IBZ May 25, 18:10 UTCMay 25, 19:10 UTC1h 0m
2026-05-25 N394AJ - May 25, 08:35 UTCMay 25, 17:10 UTC8h 35m
2026-05-17 N394AJ - May 17, 22:30 UTCMay 18, 02:25 UTC3h 55m
2026-05-15 N394AJ - May 15, 16:35 UTCMay 15, 21:20 UTC4h 45m
2026-05-10 N394AJ LDJ → FXE May 10, 06:40 UTCMay 10, 09:10 UTC2h 30m
2026-05-08 N394AJ - May 8, 10:35 UTCMay 8, 17:20 UTC6h 45m
2026-05-08 N394AJ - May 8, 05:09 UTCMay 8, 09:09 UTC4h 0m
2026-05-01 N394AJ - May 1, 06:55 UTCMay 1, 20:30 UTC13h 35m
2026-04-30 N394AJ FXE → CUN Apr 30, 05:05 UTCApr 30, 06:30 UTC1h 25m
2026-04-29 N394AJ - Apr 29, 21:35 UTCApr 29, 22:35 UTC1h 0m
2026-04-29 N394AJ - Apr 29, 18:10 UTCApr 29, 18:35 UTC25m
2026-04-27 N394AJ - Apr 27, 08:40 UTCApr 27, 08:55 UTC15m
2026-04-27 N394AJ - Apr 27, 05:30 UTCApr 27, 07:45 UTC2h 15m
2026-04-26 N394AJ - Apr 26, 19:35 UTCApr 26, 21:10 UTC1h 35m
2026-04-25 N394AJ - Apr 25, 08:50 UTCApr 25, 13:40 UTC4h 50m
2026-04-24 N394AJ HSH → HIO Apr 24, 23:55 UTCApr 25, 01:45 UTC1h 50m
2026-04-23 N394AJ - Apr 23, 17:55 UTCApr 23, 23:10 UTC5h 15m
2026-04-23 N394AJ - Apr 23, 15:20 UTCApr 23, 15:40 UTC20m
2026-04-13 N394AJ - Apr 13, 20:10 UTCApr 13, 20:45 UTC35m

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 N394AJ page for operator, model, and routing details .

Mode-S A491AE frequently asked

What is Mode-S code A491AE?
A491AE is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N394AJ.
Where is Mode-S A491AE registered?
Mode-S code A491AE 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 A491AE broadcasting right now?
No active broadcast right now. Last signal was 5d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A491AE, octal 51110656, decimal 10,785,198.
What flights does A491AE operate?
Mode-S A491AE has broadcast 1 distinct callsign, including N394AJ.