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sensors Mode-S transponder

A9C737

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N729YX · EMBRAER ERJ-170-200 (long wing) · operated by REPUBLIC AIRWAYS INC

Hex
A9C737
Octal
52343467
Decimal
11,126,583
Country
US
Tail
N729YX
Type
E75L
No current signal · last broadcast Jul 26, 20:35 UTC
Flights observed
659
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 20:35 UTC

Last known position

Most recent position reported by Mode-S A9C737.

Country allocation

The ICAO 24-bit address A9C737 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 20 distinct

Callsign Airline Flights Last seen
RPA3702 Republic Airlines 8 2026-06-11
RPA3706 - 7 2026-07-16
RPA3705 Republic Airlines 7 2026-07-26
RPA3610 - 7 2026-07-04
RPA3703 Republic Airlines 6 2026-07-18
RPA3650 Republic Airlines 6 2026-07-24
RPA3642 - 6 2026-07-11
RPA3604 - 6 2026-07-01
RPA3568 - 6 2026-07-15
RPA3531 - 6 2026-07-10
RPA3406 - 6 2026-07-05
RPA3697 - 5 2026-07-04
RPA3690 Republic Airlines 5 2026-05-25
RPA3673 - 5 2026-07-15
RPA3635 - 5 2026-06-18
RPA3625 - 5 2026-07-18
RPA3605 - 5 2026-07-17
RPA3591 Republic Airlines 5 2026-07-24
RPA3585 - 5 2026-06-17
RPA3549 Republic Airlines 5 2026-05-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RPA3705 ORD → LGA Jul 26, 19:05 UTCJul 26, 20:15 UTC1h 10m
2026-07-26 RPA3490 ORF → EWR Jul 26, 17:05 UTCJul 26, 18:05 UTC1h 0m
2026-07-26 RPA3493 PIT → EWR Jul 26, 14:55 UTCJul 26, 15:55 UTC1h 0m
2026-07-26 RPA3493 PIT → EWR Jul 26, 14:57 UTCJul 26, 15:58 UTC1h 1m
2026-07-26 RPA3498 CMH → EWR Jul 26, 12:25 UTCJul 26, 13:10 UTC45m
2026-07-26 RPA3498 CMH → EWR Jul 26, 12:22 UTCJul 26, 13:03 UTC41m
2026-07-26 RPA3524 EWR → MKE Jul 26, 09:50 UTCJul 26, 10:50 UTC1h 0m
2026-07-25 RPA3692 ITH → EWR Jul 25, 01:15 UTCJul 25, 02:25 UTC1h 10m
2026-07-24 RPA3699 EWR → ATL Jul 24, 21:35 UTCJul 24, 23:45 UTC2h 10m
2026-07-24 RPA3650 EWR → CLT Jul 24, 18:05 UTCJul 24, 20:10 UTC2h 5m
2026-07-24 RPA3591 SDF → EWR Jul 24, 15:10 UTCJul 24, 16:05 UTC55m
2026-07-24 RPA3591 SDF → EWR Jul 24, 15:19 UTCJul 24, 16:02 UTC43m
2026-07-24 RPA3505 EWR → BGR Jul 24, 12:50 UTCJul 24, 14:05 UTC1h 15m
2026-07-23 RPA3695 SAT → EWR Jul 23, 17:35 UTCJul 23, 19:25 UTC1h 50m
2026-07-23 RPA3649 EWR → MSY Jul 23, 13:00 UTCJul 23, 15:20 UTC2h 20m
2026-07-23 RPA3561 ORD → MSY Jul 23, 10:10 UTCJul 23, 11:25 UTC1h 15m
2026-07-23 RPA3506 EWR → GSP Jul 23, 00:40 UTCJul 23, 01:40 UTC1h 0m
2026-07-22 RPA3501 YYZ → EWR Jul 22, 21:00 UTCJul 22, 22:25 UTC1h 25m
2026-07-22 RPA3501 YYZ → EWR Jul 22, 20:59 UTCJul 22, 22:23 UTC1h 24m
2026-07-22 RPA3419 EWR → BOS Jul 22, 18:10 UTCJul 22, 19:45 UTC1h 35m
2026-07-22 RPA3419 EWR → BOS Jul 22, 18:14 UTCJul 22, 19:42 UTC1h 28m
2026-07-22 RPA3301 - Jul 22, 14:40 UTCJul 22, 16:00 UTC1h 20m
2026-07-21 RPA3319 SAV → PWM Jul 21, 13:30 UTCJul 21, 13:55 UTC25m
2026-07-21 RPA3683 DCA → EWR Jul 21, 10:55 UTCJul 21, 12:45 UTC1h 50m
2026-07-21 RPA3683 DCA → EWR Jul 21, 10:36 UTCJul 21, 12:44 UTC2h 8m
2026-07-21 RPA3468 CVG → EWR Jul 21, 03:20 UTCJul 21, 04:50 UTC1h 30m
2026-07-21 RPA3304 CLT → ALB Jul 21, 01:15 UTCJul 21, 02:20 UTC1h 5m
2026-07-20 RPA3302 - Jul 20, 20:00 UTCJul 20, 21:45 UTC1h 45m
2026-07-19 RPA3558 PHL → ORD Jul 19, 19:00 UTCJul 19, 19:45 UTC45m
2026-07-19 RPA3558 PHL → ORD Jul 19, 18:10 UTCJul 19, 19:47 UTC1h 37m
2026-07-18 RPA3703 YQB → EWR Jul 18, 10:15 UTCJul 18, 11:30 UTC1h 15m
2026-07-18 RPA3703 YQB → EWR Jul 18, 10:25 UTCJul 18, 11:28 UTC1h 3m
2026-07-18 RPA3625 - Jul 18, 01:54 UTCJul 18, 03:05 UTC1h 11m
2026-07-17 RPA3476 - Jul 17, 23:05 UTCJul 18, 00:29 UTC1h 25m
2026-07-17 RPA3476 RIC → EWR Jul 17, 23:05 UTCJul 18, 00:28 UTC1h 23m
2026-07-17 RPA3523 MSY → EWR Jul 17, 20:35 UTCJul 17, 22:10 UTC1h 35m
2026-07-17 RPA3523 MSY → EWR Jul 17, 20:15 UTCJul 17, 22:09 UTC1h 54m
2026-07-17 RPA3605 YYZ → ORD Jul 17, 17:35 UTCJul 17, 19:05 UTC1h 30m
2026-07-17 RPA3555 SAV → EWR Jul 17, 14:27 UTCJul 17, 15:06 UTC39m
2026-07-17 RPA3555 SAV → EWR Jul 17, 14:10 UTCJul 17, 15:25 UTC1h 15m
2026-07-17 RPA3703 - Jul 17, 10:10 UTCJul 17, 11:25 UTC1h 15m
2026-07-17 RPA3625 - Jul 17, 02:45 UTCJul 17, 03:20 UTC35m
2026-07-17 RPA3625 - Jul 17, 02:10 UTCJul 17, 03:20 UTC1h 10m
2026-07-17 RPA3476 EWR → BUF Jul 17, 01:18 UTCJul 17, 02:30 UTC1h 12m
2026-07-16 RPA3476 - Jul 16, 22:59 UTCJul 17, 00:40 UTC1h 40m
2026-07-16 RPA3523 - Jul 16, 20:09 UTCJul 16, 21:40 UTC1h 30m
2026-07-16 RPA3494 ROC → ORD Jul 16, 16:40 UTCJul 16, 18:15 UTC1h 35m
2026-07-16 RPA3647 - Jul 16, 14:40 UTCJul 16, 15:30 UTC50m
2026-07-16 RPA3647 EWR → ROC Jul 16, 14:39 UTCJul 16, 15:28 UTC49m
2026-07-16 RPA3706 - Jul 16, 11:45 UTCJul 16, 13:05 UTC1h 20m

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 N729YX page for operator, model, and routing details .

Mode-S A9C737 frequently asked

What is Mode-S code A9C737?
A9C737 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N729YX.
Where is Mode-S A9C737 registered?
Mode-S code A9C737 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 A9C737 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 20:35 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9C737, octal 52343467, decimal 11,126,583.
What flights does A9C737 operate?
Mode-S A9C737 has broadcast 20 distinct callsigns, including RPA3702, RPA3706, RPA3705, RPA3610, RPA3703.