Apparatus

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sensors Mode-S transponder

A51425

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N426YX · EMBRAER ERJ-170-200 (long wing) · operated by REPUBLIC AIRWAYS INC

Hex
A51425
Octal
51212045
Decimal
10,818,597
Country
US
Tail
N426YX
Type
E75L
No current signal · last broadcast Jul 26, 20:50 UTC
Flights observed
781
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 20:50 UTC

Last known position

Most recent position reported by Mode-S A51425.

Country allocation

The ICAO 24-bit address A51425 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
RPA4745 Republic Airlines 13 2026-07-22
RPA4698 - 9 2026-07-06
RPA4453 - 9 2026-06-28
RPA4774 - 8 2026-07-12
RPA4678 Republic Airlines 8 2026-06-13
RPA4579 Republic Airlines 8 2026-07-26
RPA4413 - 8 2026-07-11
RPA4758 - 7 2026-06-28
RPA4491 - 7 2026-07-02
RPA4450 Republic Airlines 7 2026-07-26
RPA4781 Republic Airlines 6 2026-06-05
RPA4764 - 6 2026-07-04
RPA4747 - 6 2026-06-25
RPA4717 Republic Airlines 6 2026-06-07
RPA4640 Republic Airlines 6 2026-07-21
RPA4623 Republic Airlines 6 2026-06-09
RPA4615 Republic Airlines 6 2026-07-23
RPA4500 Republic Airlines 6 2026-05-25
RPA4493 Republic Airlines 6 2026-07-19
RPA4484 - 6 2026-06-30

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RPA4710 PHL → DCA Jul 26, 19:00 UTCJul 26, 20:45 UTC1h 45m
2026-07-26 RPA4568 PHL → IND Jul 26, 16:25 UTCJul 26, 17:30 UTC1h 5m
2026-07-26 RPA4579 ATL → LGA Jul 26, 14:15 UTCJul 26, 15:15 UTC1h 0m
2026-07-26 RPA4411 BOS → IND Jul 26, 11:05 UTCJul 26, 13:00 UTC1h 55m
2026-07-26 RPA4411 BOS → IND Jul 26, 11:05 UTCJul 26, 12:48 UTC1h 43m
2026-07-26 RPA4629 DCA → BGR Jul 26, 05:20 UTCJul 26, 07:15 UTC1h 56m
2026-07-26 RPA4450 PIT → PHL Jul 26, 02:50 UTCJul 26, 04:20 UTC1h 30m
2026-07-25 RPA4450 PIT → PHL Jul 25, 23:55 UTCJul 26, 02:05 UTC2h 10m
2026-07-25 RPA4527 MHT → CLT Jul 25, 17:15 UTCJul 25, 20:05 UTC2h 50m
2026-07-25 RPA4527 MHT → CLT Jul 25, 13:35 UTCJul 25, 16:15 UTC2h 40m
2026-07-25 RPA4364 MSP → PHL Jul 25, 10:25 UTCJul 25, 11:45 UTC1h 20m
2026-07-25 RPA4544 LGA → IAH Jul 25, 02:20 UTCJul 25, 03:15 UTC55m
2026-07-25 RPA4544 LGA → IAH Jul 25, 02:18 UTCJul 25, 03:20 UTC1h 2m
2026-07-25 RPA4736 LGA → BUF Jul 25, 00:20 UTCJul 25, 01:25 UTC1h 5m
2026-07-24 RPA4736 LGA → BUF Jul 24, 22:25 UTCJul 24, 23:25 UTC1h 0m
2026-07-24 RPA4514 RDU → PIT Jul 24, 20:35 UTCJul 24, 21:20 UTC45m
2026-07-24 RPA4514 RDU → PIT Jul 24, 18:30 UTCJul 24, 19:15 UTC45m
2026-07-24 RPA4515 IND → LGA Jul 24, 15:15 UTCJul 24, 16:40 UTC1h 25m
2026-07-24 RPA4515 IND → LGA Jul 24, 13:15 UTCJul 24, 14:25 UTC1h 10m
2026-07-24 RPA4538 JFK → DCA Jul 24, 10:55 UTCJul 24, 11:40 UTC45m
2026-07-24 RPA4417 CHO → LGA Jul 24, 00:35 UTCJul 24, 01:45 UTC1h 10m
2026-07-23 RPA4518 PWM → DCA Jul 23, 21:40 UTCJul 23, 23:10 UTC1h 30m
2026-07-23 RPA4676 DCA → CVG Jul 23, 18:50 UTCJul 23, 19:45 UTC55m
2026-07-23 RPA4676 DCA → CVG Jul 23, 18:48 UTCJul 23, 19:44 UTC56m
2026-07-23 RPA4676 DCA → CVG Jul 23, 16:45 UTCJul 23, 17:35 UTC50m
2026-07-23 RPA4480 LGA → PIT Jul 23, 14:15 UTCJul 23, 15:20 UTC1h 5m
2026-07-23 RPA4532 DCA → PIT Jul 23, 12:20 UTCJul 23, 13:15 UTC55m
2026-07-23 RPA4615 JFK → BNA Jul 23, 01:55 UTCJul 23, 03:15 UTC1h 20m
2026-07-23 RPA4615 JFK → BNA Jul 23, 01:51 UTCJul 23, 03:20 UTC1h 29m
2026-07-22 RPA4745 PHL → BUF Jul 22, 22:55 UTCJul 22, 23:50 UTC55m
2026-07-22 RPA4745 PHL → BUF Jul 22, 20:40 UTCJul 22, 21:50 UTC1h 10m
2026-07-22 RPA4412 PHL → DTW Jul 22, 17:45 UTCJul 22, 18:50 UTC1h 5m
2026-07-22 RPA4412 PHL → DTW Jul 22, 17:40 UTCJul 22, 18:39 UTC59m
2026-07-22 RPA4412 PHL → DTW Jul 22, 15:45 UTCJul 22, 16:35 UTC50m
2026-07-22 RPA4633 LGA → ORD Jul 22, 12:25 UTCJul 22, 14:25 UTC2h 0m
2026-07-22 RPA4633 LGA → ORD Jul 22, 12:22 UTCJul 22, 14:12 UTC1h 50m
2026-07-22 RPA4615 JFK → BNA Jul 22, 01:45 UTCJul 22, 04:30 UTC2h 45m
2026-07-22 RPA4615 JFK → BNA Jul 22, 01:42 UTCJul 22, 04:29 UTC2h 47m
2026-07-21 RPA4745 - Jul 21, 22:30 UTCJul 21, 23:35 UTC1h 5m
2026-07-21 RPA4745 MCI → ORD Jul 21, 22:28 UTCJul 21, 23:32 UTC1h 4m
2026-07-21 RPA4745 - Jul 21, 20:20 UTCJul 21, 21:20 UTC1h 0m
2026-07-21 RPA4746 LGA → ORF Jul 21, 16:05 UTCJul 21, 17:55 UTC1h 50m
2026-07-21 RPA4746 LGA → ORF Jul 21, 16:00 UTCJul 21, 17:54 UTC1h 54m
2026-07-21 RPA4746 LGA → ORF Jul 21, 13:25 UTCJul 21, 15:05 UTC1h 40m
2026-07-21 RPA4651 JFK → ORF Jul 21, 11:30 UTCJul 21, 12:05 UTC35m
2026-07-21 RPA4651 JFK → ORF Jul 21, 10:10 UTCJul 21, 12:05 UTC1h 55m
2026-07-21 RPA4651 JFK → ORF Jul 21, 10:09 UTCJul 21, 11:13 UTC1h 4m
2026-07-21 RPA4640 JFK → PIT Jul 21, 03:05 UTCJul 21, 04:20 UTC1h 15m
2026-07-21 RPA4640 JFK → PIT Jul 21, 03:01 UTCJul 21, 04:20 UTC1h 19m
2026-07-20 RPA4537 STL → ORD Jul 20, 23:15 UTCJul 21, 00:40 UTC1h 24m

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 N426YX page for operator, model, and routing details .

Mode-S A51425 frequently asked

What is Mode-S code A51425?
A51425 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N426YX.
Where is Mode-S A51425 registered?
Mode-S code A51425 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 A51425 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 20:50 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A51425, octal 51212045, decimal 10,818,597.
What flights does A51425 operate?
Mode-S A51425 has broadcast 20 distinct callsigns, including RPA4745, RPA4698, RPA4453, RPA4774, RPA4678.