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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
Transponder active on ground
Flights observed
714
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 20:00 UTC

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
RPA4665 - 10 2026-07-17
RPA4643 - 9 2026-07-01
RPA4508 - 8 2026-07-20
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
RPA4735 - 6 2026-07-16
RPA4724 - 6 2026-07-18
RPA4663 - 6 2026-07-18
RPA4655 Republic Airlines 6 2026-05-14
RPA4652 - 6 2026-07-17
RPA4626 - 6 2026-07-09
RPA4580 Republic Airlines 6 2026-07-25
RPA4561 Republic Airlines 6 2026-05-21
RPA4560 - 6 2026-07-13
RPA4537 - 6 2026-07-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RPA4429 JFK → RDU Jul 26, 19:00 UTCJul 26, 20:00 UTC1h 0m
2026-07-26 RPA4394 DCA → PHL Jul 26, 16:20 UTCJul 26, 17:15 UTC55m
2026-07-26 RPA4394 DCA → PHL Jul 26, 16:18 UTCJul 26, 17:56 UTC1h 38m
2026-07-26 RPA4394 DCA → PHL Jul 26, 13:45 UTCJul 26, 15:00 UTC1h 15m
2026-07-25 RPA4580 BOS → JFK Jul 25, 18:25 UTCJul 25, 19:55 UTC1h 30m
2026-07-25 RPA4580 BOS → JFK Jul 25, 18:19 UTCJul 25, 19:47 UTC1h 28m
2026-07-25 RPA4580 BOS → JFK Jul 25, 15:20 UTCJul 25, 16:50 UTC1h 30m
2026-07-25 RPA4669 MIA → BTV Jul 25, 11:55 UTCJul 25, 14:05 UTC2h 10m
2026-07-24 RPA4728 CMH → LGA Jul 24, 23:20 UTCJul 25, 01:30 UTC2h 10m
2026-07-24 RPA4619 ORF → LGA Jul 24, 19:25 UTCJul 24, 22:00 UTC2h 35m
2026-07-24 RPA4619 ORF → LGA Jul 24, 15:30 UTCJul 24, 18:25 UTC2h 55m
2026-07-24 RPA4564 SDF → BOS Jul 24, 11:15 UTCJul 24, 13:30 UTC2h 15m
2026-07-24 RPA4696 MSP → PHL Jul 24, 00:45 UTCJul 24, 03:15 UTC2h 30m
2026-07-23 RPA4378 BOS → JFK Jul 23, 22:55 UTCJul 23, 23:50 UTC55m
2026-07-23 RPA4378 BOS → JFK Jul 23, 22:54 UTCJul 23, 23:41 UTC47m
2026-07-23 RPA4378 BOS → JFK Jul 23, 20:10 UTCJul 23, 21:05 UTC55m
2026-07-23 RPA4606 ATL → LGA Jul 23, 16:35 UTCJul 23, 18:30 UTC1h 55m
2026-07-23 RPA4606 LGA → ATL Jul 23, 13:35 UTCJul 23, 15:30 UTC1h 55m
2026-07-23 RPA4451 RIC → LGA Jul 23, 10:15 UTCJul 23, 10:55 UTC40m
2026-07-23 RPA4345 BOS → IND Jul 23, 02:46 UTCJul 23, 03:49 UTC1h 3m
2026-07-23 RPA4345 BOS → IND Jul 23, 02:50 UTCJul 23, 03:40 UTC50m
2026-07-22 RPA4524 MSP → LGA Jul 22, 22:15 UTCJul 23, 00:45 UTC2h 30m
2026-07-22 RPA4524 MSP → LGA Jul 22, 18:40 UTCJul 22, 21:20 UTC2h 40m
2026-07-22 RPA4428 LGA → LIT Jul 22, 16:05 UTCJul 22, 17:20 UTC1h 15m
2026-07-22 RPA4428 LGA → LIT Jul 22, 13:45 UTCJul 22, 15:05 UTC1h 20m
2026-07-21 RPA4494 RDU → LGA Jul 21, 14:30 UTCJul 21, 15:40 UTC1h 10m
2026-07-21 RPA4494 RDU → LGA Jul 21, 14:29 UTCJul 21, 15:38 UTC1h 9m
2026-07-21 RPA4494 LGA → RDU Jul 21, 10:45 UTCJul 21, 12:00 UTC1h 15m
2026-07-20 RPA4470 LGA → ATL Jul 20, 22:05 UTCJul 21, 01:00 UTC2h 55m
2026-07-20 RPA4470 LGA → ATL Jul 20, 17:45 UTCJul 20, 20:55 UTC3h 10m
2026-07-20 RPA4508 STL → LGA Jul 20, 14:25 UTCJul 20, 16:25 UTC2h 0m
2026-07-20 RPA4508 STL → LGA Jul 20, 14:25 UTCJul 20, 16:24 UTC1h 59m
2026-07-20 RPA4508 LGA → STL Jul 20, 11:30 UTCJul 20, 13:40 UTC2h 10m
2026-07-20 RPA4397 PWM → DCA Jul 20, 00:15 UTCJul 20, 01:05 UTC50m
2026-07-20 RPA4397 PWM → DCA Jul 20, 00:13 UTCJul 20, 01:01 UTC48m
2026-07-19 RPA4346 LGA → STL Jul 19, 21:59 UTCJul 19, 22:34 UTC35m
2026-07-19 RPA4346 LGA → STL Jul 19, 22:00 UTCJul 19, 22:35 UTC35m
2026-07-19 RPA4371 JFK → RDU Jul 19, 18:35 UTCJul 19, 20:10 UTC1h 35m
2026-07-19 RPA4371 JFK → RDU Jul 19, 18:34 UTCJul 19, 20:09 UTC1h 35m
2026-07-19 RPA4413 - Jul 19, 15:15 UTCJul 19, 15:45 UTC30m
2026-07-19 RPA4413 - Jul 19, 14:15 UTCJul 19, 15:45 UTC1h 30m
2026-07-19 RPA4413 BUF → ORD Jul 19, 14:14 UTCJul 19, 14:59 UTC45m
2026-07-19 RPA4413 - Jul 19, 12:05 UTCJul 19, 13:10 UTC1h 5m
2026-07-19 RPA9774 LGA → IND Jul 19, 01:05 UTCJul 19, 03:50 UTC2h 45m
2026-07-18 RPA9695 CMH → TUL Jul 18, 22:00 UTCJul 19, 00:15 UTC2h 15m
2026-07-18 RPA9945 LGA → IND Jul 18, 19:55 UTCJul 18, 21:10 UTC1h 15m
2026-07-18 RPA4746 - Jul 18, 16:45 UTCJul 18, 18:40 UTC1h 55m
2026-07-18 RPA4746 - Jul 18, 13:35 UTCJul 18, 15:05 UTC1h 30m
2026-07-18 RPA4659 DCA → PWM Jul 18, 10:00 UTCJul 18, 11:40 UTC1h 40m
2026-07-18 RPA4663 - Jul 18, 04:25 UTCJul 18, 05:45 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 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?
Mode-S A537ED is currently broadcasting from the ground.
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 RPA4665, RPA4643, RPA4508, RPA4501, RPA4403.