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sensors Mode-S transponder

A537ED

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N435YX · EMBRAER ERJ-170-200 (long wing) · operated by REPUBLIC AIRWAYS INC

Hex
A537ED
Octal
51233755
Decimal
10,827,757
Country
US
Tail
N435YX
Type
E75L
No current signal · last broadcast 7h ago
Flights observed
636
Distinct callsigns
20
Country
US
Last broadcast
7h ago

Last known position

Most recent position reported by Mode-S A537ED.

Country allocation

The ICAO 24-bit address A537ED 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
RPA4643 - 9 2026-07-01
RPA4665 - 8 2026-06-30
RPA4501 - 8 2026-07-05
RPA4403 - 8 2026-07-12
RPA4364 - 8 2026-07-02
RPA4729 - 7 2026-06-30
RPA4545 - 7 2026-07-10
RPA4450 - 7 2026-06-27
RPA4432 Republic Airlines 7 2026-07-01
RPA4655 Republic Airlines 6 2026-05-14
RPA4626 - 6 2026-07-09
RPA4561 Republic Airlines 6 2026-05-21
RPA4560 - 6 2026-07-13
RPA4354 Republic Airlines 6 2026-06-25
RPA4774 Republic Airlines 5 2026-05-27
RPA4767 Republic Airlines 5 2026-06-01
RPA4740 - 5 2026-07-12
RPA4738 - 5 2026-06-28
RPA4582 Republic Airlines 5 2026-05-08
RPA4553 - 5 2026-07-08

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 RPA4470 - Jul 13, 22:10 UTCJul 14, 01:20 UTC3h 10m
2026-07-13 RPA4470 LGA → OKC Jul 13, 17:45 UTCJul 13, 20:40 UTC2h 55m
2026-07-13 RPA4508 STL → LGA Jul 13, 14:30 UTCJul 13, 16:40 UTC2h 10m
2026-07-13 RPA4508 LGA → STL Jul 13, 11:10 UTCJul 13, 13:15 UTC2h 5m
2026-07-13 RPA4560 - Jul 13, 01:10 UTCJul 13, 02:15 UTC1h 5m
2026-07-13 RPA4560 RDU → LGA Jul 13, 01:06 UTCJul 13, 02:15 UTC1h 9m
2026-07-12 RPA4518 ORD → RDU Jul 12, 21:20 UTCJul 12, 23:00 UTC1h 40m
2026-07-12 RPA4518 ORD → RDU Jul 12, 21:20 UTCJul 12, 22:37 UTC1h 17m
2026-07-12 RPA4740 - Jul 12, 17:40 UTCJul 12, 19:15 UTC1h 35m
2026-07-12 RPA4740 JAX → ORD Jul 12, 17:38 UTCJul 12, 19:46 UTC2h 8m
2026-07-12 RPA4740 - Jul 12, 14:30 UTCJul 12, 16:25 UTC1h 55m
2026-07-12 RPA4391 - Jul 12, 11:10 UTCJul 12, 13:25 UTC2h 15m
2026-07-12 RPA4403 - Jul 12, 01:15 UTCJul 12, 03:15 UTC2h 0m
2026-07-12 RPA4403 ORD → PWM Jul 12, 01:14 UTCJul 12, 03:14 UTC2h 0m
2026-07-11 RPA4724 - Jul 11, 22:20 UTCJul 11, 23:15 UTC55m
2026-07-11 RPA4724 OMA → ORD Jul 11, 22:18 UTCJul 11, 23:28 UTC1h 10m
2026-07-11 RPA4724 - Jul 11, 19:55 UTCJul 11, 21:00 UTC1h 5m
2026-07-11 RPA4500 - Jul 11, 16:25 UTCJul 11, 18:10 UTC1h 45m
2026-07-11 RPA4500 - Jul 11, 13:55 UTCJul 11, 15:35 UTC1h 40m
2026-07-11 RPA4622 - Jul 11, 11:00 UTCJul 11, 12:05 UTC1h 5m
2026-07-11 RPA4466 - Jul 11, 01:45 UTCJul 11, 03:10 UTC1h 25m
2026-07-11 RPA4466 PHL → PHL Jul 11, 01:05 UTCJul 11, 01:25 UTC20m
2026-07-11 RPA4466 PHL → PHL Jul 11, 00:10 UTCJul 11, 00:15 UTC5m
2026-07-10 RPA4652 YYZ → PHL Jul 10, 22:50 UTCJul 10, 23:45 UTC55m
2026-07-10 RPA4652 PHL → YYZ Jul 10, 19:44 UTCJul 10, 20:43 UTC59m
2026-07-10 RPA4735 - Jul 10, 17:20 UTCJul 10, 18:10 UTC50m
2026-07-10 RPA4735 ACK → PHL Jul 10, 17:13 UTCJul 10, 18:09 UTC56m
2026-07-10 RPA4735 - Jul 10, 15:15 UTCJul 10, 16:05 UTC50m
2026-07-10 RPA4735 PHL → PHL Jul 10, 14:55 UTCJul 10, 15:00 UTC5m
2026-07-10 RPA4637 - Jul 10, 03:40 UTCJul 10, 03:45 UTC5m
2026-07-10 RPA4545 - Jul 10, 00:35 UTCJul 10, 01:50 UTC1h 15m
2026-07-10 RPA4545 ACK → PHL Jul 10, 00:33 UTCJul 10, 01:47 UTC1h 14m
2026-07-09 RPA4545 PHL → ACK Jul 9, 20:45 UTCJul 9, 21:54 UTC1h 9m
2026-07-09 RPA4545 - Jul 9, 20:45 UTCJul 9, 21:55 UTC1h 10m
2026-07-09 RPA4602 - Jul 9, 14:55 UTCJul 9, 15:50 UTC55m
2026-07-09 RPA4649 DCA → MVY Jul 9, 13:07 UTCJul 9, 14:07 UTC1h 0m
2026-07-09 RPA4649 DCA → MVY Jul 9, 13:10 UTCJul 9, 14:10 UTC1h 0m
2026-07-09 RPA4626 IND → DCA Jul 9, 10:05 UTCJul 9, 11:25 UTC1h 20m
2026-07-09 RPA4626 IND → DCA Jul 9, 10:05 UTCJul 9, 11:24 UTC1h 19m
2026-07-09 RPA4520 - Jul 9, 00:25 UTCJul 9, 01:40 UTC1h 15m
2026-07-08 RPA4553 - Jul 8, 22:05 UTCJul 8, 23:15 UTC1h 10m
2026-07-08 RPA4553 - Jul 8, 19:50 UTCJul 8, 20:45 UTC55m
2026-07-08 RPA4431 - Jul 8, 16:30 UTCJul 8, 18:25 UTC1h 55m
2026-07-08 RPA4431 - Jul 8, 13:25 UTCJul 8, 15:35 UTC2h 10m
2026-07-08 RPA4612 LGA → DCA Jul 8, 10:15 UTCJul 8, 11:00 UTC45m
2026-07-08 RPA4560 - Jul 8, 02:50 UTCJul 8, 03:55 UTC1h 5m
2026-07-08 RPA4560 RDU → LGA Jul 8, 02:48 UTCJul 8, 03:51 UTC1h 3m
2026-07-08 RPA4596 - Jul 8, 01:25 UTCJul 8, 01:45 UTC20m
2026-07-07 RPA4596 - Jul 7, 22:25 UTCJul 8, 00:25 UTC2h 0m
2026-07-07 RPA4372 LGA → BNA Jul 7, 19:20 UTCJul 7, 21:20 UTC2h 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 N435YX page for operator, model, and routing details .

Mode-S A537ED frequently asked

What is Mode-S code A537ED?
A537ED is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N435YX.
Where is Mode-S A537ED registered?
Mode-S code A537ED 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 A537ED broadcasting right now?
No active broadcast right now. Last signal was 7h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A537ED, octal 51233755, decimal 10,827,757.
What flights does A537ED operate?
Mode-S A537ED has broadcast 20 distinct callsigns, including RPA4643, RPA4665, RPA4501, RPA4403, RPA4364.