sensors Mode-S transponder

A9C66A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N729QS · BOMBARDIER BD-100 Challenger 350 · operated by MEREDYTH SOUTH LLC, ROZWAT CHARLES A TRUSTEE, ROZWAT CAROLYN H TRUSTEE, UNICORN HRO LLC, ECLINICALWORKS LLC, ROCK DOUGLAS L

Hex
A9C66A
Octal
52343152
Decimal
11,126,378
Country
US
Tail
N729QS
Type
CL35
No current signal · last broadcast Jul 26, 22:30 UTC
Flights observed
155
Distinct callsigns
2
Country
US
Last broadcast
Jul 26, 22:30 UTC

Last known position

Most recent position reported by Mode-S A9C66A.

Country allocation

The ICAO 24-bit address A9C66A 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 2 distinct

Callsign Airline Flights Last seen
EJA729 NetJets 143 2026-07-26
N729QS - 12 2026-07-05

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 EJA729 TEB → VNY Jul 26, 18:10 UTCJul 26, 22:30 UTC4h 20m
2026-07-26 EJA729 TEB → VNY Jul 26, 02:00 UTCJul 26, 03:00 UTC1h 0m
2026-07-25 EJA729 TEB → VNY Jul 25, 21:10 UTCJul 25, 22:30 UTC1h 20m
2026-07-25 EJA729 TEB → VNY Jul 25, 03:20 UTCJul 25, 04:20 UTC1h 0m
2026-07-24 EJA729 TEB → VNY Jul 24, 23:50 UTCJul 25, 00:50 UTC1h 0m
2026-07-24 EJA729 TEB → VNY Jul 24, 18:10 UTCJul 24, 22:00 UTC3h 50m
2026-07-23 EJA729 TEB → VNY Jul 23, 14:10 UTCJul 23, 20:20 UTC6h 10m
2026-07-23 EJA729 TEB → VNY Jul 23, 12:05 UTCJul 23, 13:05 UTC1h 0m
2026-07-19 EJA729 TEB → VNY Jul 19, 20:15 UTCJul 19, 21:55 UTC1h 40m
2026-07-19 EJA729 TEB → VNY Jul 19, 16:50 UTCJul 19, 17:35 UTC45m
2026-07-19 EJA729 - Jul 19, 13:25 UTCJul 19, 14:15 UTC50m
2026-07-19 EJA729 - Jul 19, 10:30 UTCJul 19, 11:25 UTC55m
2026-07-17 EJA729 - Jul 17, 19:45 UTCJul 17, 20:35 UTC50m
2026-07-17 EJA729 - Jul 17, 16:10 UTCJul 17, 18:40 UTC2h 30m
2026-07-17 EJA729 - Jul 17, 13:29 UTCJul 17, 14:39 UTC1h 10m
2026-07-16 EJA729 - Jul 16, 21:05 UTCJul 16, 22:55 UTC1h 50m
2026-07-16 EJA729 - Jul 16, 14:40 UTCJul 16, 19:45 UTC5h 5m
2026-07-16 EJA729 - Jul 16, 03:30 UTCJul 16, 04:45 UTC1h 15m
2026-07-15 EJA729 BOS → SFO Jul 15, 20:40 UTCJul 16, 02:20 UTC5h 40m
2026-07-15 EJA729 - Jul 15, 15:45 UTCJul 15, 16:55 UTC1h 10m
2026-07-15 EJA729 - Jul 15, 14:30 UTCJul 15, 15:10 UTC40m
2026-07-15 EJA729 - Jul 15, 12:50 UTCJul 15, 13:50 UTC1h 0m
2026-07-15 EJA729 - Jul 15, 11:30 UTCJul 15, 11:45 UTC15m
2026-07-14 EJA729 - Jul 14, 20:30 UTCJul 14, 21:25 UTC55m
2026-07-14 EJA729 - Jul 14, 19:00 UTCJul 14, 19:35 UTC35m
2026-07-14 EJA729 - Jul 14, 15:35 UTCJul 14, 16:20 UTC45m
2026-07-14 EJA729 - Jul 14, 13:00 UTCJul 14, 13:25 UTC25m
2026-07-14 EJA729 SJC → BOS Jul 14, 06:05 UTCJul 14, 11:30 UTC5h 25m
2026-07-13 EJA729 - Jul 13, 19:50 UTCJul 13, 20:20 UTC30m
2026-07-13 EJA729 SLC → STS Jul 13, 17:15 UTCJul 13, 18:35 UTC1h 20m
2026-07-13 EJA729 - Jul 13, 12:05 UTCJul 13, 16:30 UTC4h 25m
2026-07-12 EJA729 - Jul 12, 21:30 UTCJul 12, 22:10 UTC40m
2026-07-12 EJA729 - Jul 12, 18:15 UTCJul 12, 19:30 UTC1h 15m
2026-07-12 EJA729 - Jul 12, 15:50 UTCJul 12, 17:20 UTC1h 30m
2026-07-11 EJA729 - Jul 11, 14:10 UTCJul 11, 17:40 UTC3h 30m
2026-07-11 EJA729 - Jul 11, 00:00 UTCJul 11, 00:10 UTC10m
2026-07-10 EJA729 - Jul 10, 19:00 UTCJul 10, 21:20 UTC2h 21m
2026-07-10 EJA729 - Jul 10, 16:10 UTCJul 10, 18:00 UTC1h 50m
2026-07-10 EJA729 - Jul 10, 14:05 UTCJul 10, 14:35 UTC30m
2026-07-10 EJA729 - Jul 10, 11:40 UTCJul 10, 13:00 UTC1h 20m
2026-07-09 EJA729 - Jul 9, 19:40 UTCJul 9, 21:05 UTC1h 25m
2026-07-09 EJA729 - Jul 9, 18:00 UTCJul 9, 19:00 UTC1h 0m
2026-07-09 EJA729 BED → ILG Jul 9, 10:40 UTCJul 9, 11:45 UTC1h 5m
2026-07-08 EJA729 - Jul 8, 22:05 UTCJul 8, 22:45 UTC40m
2026-07-08 EJA729 - Jul 8, 17:35 UTCJul 8, 20:55 UTC3h 20m
2026-07-07 EJA729 - Jul 7, 22:40 UTCJul 8, 20:55 UTC22h 15m
2026-07-07 EJA729 - Jul 7, 20:30 UTCJul 7, 21:10 UTC40m
2026-07-07 EJA729 - Jul 7, 17:25 UTCJul 7, 17:50 UTC25m
2026-07-07 EJA729 - Jul 7, 14:25 UTCJul 7, 16:40 UTC2h 15m
2026-07-06 EJA729 - Jul 6, 21:40 UTCJul 7, 16:40 UTC19h 0m

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 N729QS page for operator, model, and routing details .

Mode-S A9C66A frequently asked

What is Mode-S code A9C66A?
A9C66A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N729QS.
Where is Mode-S A9C66A registered?
Mode-S code A9C66A 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 A9C66A broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:30 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9C66A, octal 52343152, decimal 11,126,378.
What flights does A9C66A operate?
Mode-S A9C66A has broadcast 2 distinct callsigns, including EJA729, N729QS.