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sensors Mode-S transponder

A4C527

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N406YX · EMBRAER ERJ-170-200 (long wing) · operated by REPUBLIC AIRWAYS INC

Hex
A4C527
Octal
51142447
Decimal
10,798,375
Country
US
Tail
N406YX
Type
E75L
No current signal · last broadcast Jul 26, 21:45 UTC
Flights observed
758
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:45 UTC

Last known position

Most recent position reported by Mode-S A4C527.

Country allocation

The ICAO 24-bit address A4C527 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
RPA4407 Republic Airlines 11 2026-07-24
RPA4740 Republic Airlines 9 2026-06-08
RPA4735 - 9 2026-07-13
RPA4652 - 9 2026-07-13
RPA4416 - 9 2026-07-01
RPA4727 - 8 2026-07-20
RPA4583 Republic Airlines 8 2026-05-20
RPA4561 Republic Airlines 8 2026-07-23
RPA4510 Republic Airlines 8 2026-07-22
RPA4439 Republic Airlines 8 2026-07-24
RPA4746 Republic Airlines 7 2026-07-20
RPA4711 - 7 2026-07-13
RPA4536 - 7 2026-07-07
RPA4434 Republic Airlines 7 2026-07-24
RPA4418 - 7 2026-07-06
RPA4361 Republic Airlines 7 2026-07-24
RPA4336 - 7 2026-07-12
RPA4728 Republic Airlines 6 2026-04-25
RPA4590 - 6 2026-07-08
RPA4579 Republic Airlines 6 2026-05-06

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RPA4506 BNA → LGA Jul 26, 20:55 UTCJul 26, 21:45 UTC50m
2026-07-26 RPA4565 DCA → PWM Jul 26, 18:33 UTCJul 26, 19:28 UTC55m
2026-07-26 RPA4565 DCA → PWM Jul 26, 15:50 UTCJul 26, 16:25 UTC35m
2026-07-26 RPA4656 LGA → BNA Jul 26, 12:15 UTCJul 26, 14:50 UTC2h 35m
2026-07-26 RPA4656 LGA → BNA Jul 26, 12:10 UTCJul 26, 14:49 UTC2h 39m
2026-07-26 RPA4571 ATL → LGA Jul 26, 03:00 UTCJul 26, 05:00 UTC2h 0m
2026-07-25 RPA4548 PHL → PVD Jul 25, 22:25 UTCJul 26, 00:40 UTC2h 15m
2026-07-25 RPA4562 BDL → DCA Jul 25, 20:25 UTCJul 25, 21:10 UTC45m
2026-07-25 RPA4488 LGA → ORF Jul 25, 16:20 UTCJul 25, 18:30 UTC2h 10m
2026-07-25 RPA4488 LGA → ORF Jul 25, 13:35 UTCJul 25, 15:25 UTC1h 50m
2026-07-25 RPA4427 LGA → IND Jul 25, 10:35 UTCJul 25, 11:45 UTC1h 10m
2026-07-25 RPA4427 LGA → IND Jul 25, 10:34 UTCJul 25, 11:39 UTC1h 5m
2026-07-25 RPA4763 MIA → ALB Jul 25, 02:10 UTCJul 25, 02:55 UTC45m
2026-07-24 RPA4402 IND → ORD Jul 24, 23:35 UTCJul 25, 00:25 UTC50m
2026-07-24 RPA4402 IND → ORD Jul 24, 21:25 UTCJul 24, 22:25 UTC1h 0m
2026-07-24 RPA4407 DCA → ALB Jul 24, 19:15 UTCJul 24, 20:25 UTC1h 10m
2026-07-24 RPA4407 DCA → ALB Jul 24, 16:25 UTCJul 24, 17:50 UTC1h 25m
2026-07-24 RPA4434 AGS → BOS Jul 24, 14:00 UTCJul 24, 15:20 UTC1h 20m
2026-07-24 RPA4439 YYZ → LGA Jul 24, 12:00 UTCJul 24, 12:30 UTC30m
2026-07-24 RPA4439 YYZ → LGA Jul 24, 11:55 UTCJul 24, 12:26 UTC31m
2026-07-24 RPA4487 PHL → DCA Jul 24, 09:40 UTCJul 24, 10:50 UTC1h 10m
2026-07-24 RPA4487 PHL → DCA Jul 24, 09:39 UTCJul 24, 10:49 UTC1h 10m
2026-07-24 RPA4361 BTV → DCA Jul 24, 02:10 UTCJul 24, 03:20 UTC1h 10m
2026-07-23 RPA4749 PHL → DCA Jul 23, 22:10 UTCJul 23, 22:55 UTC45m
2026-07-23 RPA4749 PHL → DCA Jul 23, 20:45 UTCJul 23, 21:35 UTC50m
2026-07-23 RPA4430 IND → DCA Jul 23, 17:00 UTCJul 23, 18:00 UTC1h 0m
2026-07-23 RPA4561 CMH → LGA Jul 23, 15:09 UTCJul 23, 15:42 UTC33m
2026-07-23 RPA4561 CMH → LGA Jul 23, 15:10 UTCJul 23, 15:55 UTC45m
2026-07-23 RPA4613 BDL → DCA Jul 23, 12:05 UTCJul 23, 13:30 UTC1h 25m
2026-07-22 RPA4458 JFK → ORF Jul 22, 23:45 UTCJul 23, 01:30 UTC1h 45m
2026-07-22 RPA4758 JFK → DCA Jul 22, 20:15 UTCJul 22, 21:15 UTC1h 0m
2026-07-22 RPA4453 LGA → LIT Jul 22, 17:50 UTCJul 22, 19:10 UTC1h 20m
2026-07-22 RPA4476 - Jul 22, 14:45 UTCJul 22, 15:55 UTC1h 10m
2026-07-22 RPA4387 LGA → CLE Jul 22, 12:35 UTCJul 22, 13:45 UTC1h 10m
2026-07-22 RPA4693 SDF → LGA Jul 22, 11:10 UTCJul 22, 11:20 UTC10m
2026-07-22 RPA4510 CMH → PHL Jul 22, 04:55 UTCJul 22, 05:25 UTC30m
2026-07-22 RPA4563 BOS → SDF Jul 22, 00:55 UTCJul 22, 03:20 UTC2h 25m
2026-07-21 RPA4518 PWM → DCA Jul 21, 21:25 UTCJul 21, 23:15 UTC1h 50m
2026-07-21 RPA4756 - Jul 21, 18:00 UTCJul 21, 20:10 UTC2h 10m
2026-07-21 RPA4756 RDU → ORD Jul 21, 17:58 UTCJul 21, 19:45 UTC1h 47m
2026-07-21 RPA4756 - Jul 21, 14:55 UTCJul 21, 16:25 UTC1h 30m
2026-07-21 RPA4683 LGA → CHO Jul 21, 10:55 UTCJul 21, 13:05 UTC2h 10m
2026-07-21 RPA4510 CMH → PHL Jul 21, 00:35 UTCJul 21, 02:20 UTC1h 45m
2026-07-20 RPA4727 MSP → ORD Jul 20, 21:25 UTCJul 20, 22:45 UTC1h 20m
2026-07-20 RPA4727 MSP → ORD Jul 20, 21:22 UTCJul 20, 22:34 UTC1h 12m
2026-07-20 RPA4727 - Jul 20, 19:30 UTCJul 20, 20:30 UTC1h 0m
2026-07-20 RPA4746 LGA → ORF Jul 20, 15:55 UTCJul 20, 17:30 UTC1h 35m
2026-07-20 RPA4746 LGA → ORF Jul 20, 13:20 UTCJul 20, 14:45 UTC1h 25m
2026-07-20 RPA4651 JFK → ORF Jul 20, 10:05 UTCJul 20, 11:30 UTC1h 25m
2026-07-20 RPA4640 - Jul 20, 02:35 UTCJul 20, 03:50 UTC1h 15m

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 N406YX page for operator, model, and routing details .

Mode-S A4C527 frequently asked

What is Mode-S code A4C527?
A4C527 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N406YX.
Where is Mode-S A4C527 registered?
Mode-S code A4C527 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 A4C527 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4C527, octal 51142447, decimal 10,798,375.
What flights does A4C527 operate?
Mode-S A4C527 has broadcast 20 distinct callsigns, including RPA4407, RPA4740, RPA4735, RPA4652, RPA4416.