Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A4F05D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N417YX · EMBRAER ERJ-170-200 (long wing) · operated by REPUBLIC AIRWAYS INC

Hex
A4F05D
Octal
51170135
Decimal
10,809,437
Country
US
Tail
N417YX
Type
E75L
No current signal · last broadcast Jul 26, 19:55 UTC
Flights observed
639
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 19:55 UTC

Last known position

Most recent position reported by Mode-S A4F05D.

Country allocation

The ICAO 24-bit address A4F05D 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
RPA4666 Republic Airlines 10 2026-07-25
RPA4774 - 9 2026-07-12
RPA4757 - 8 2026-07-02
RPA4561 - 8 2026-06-16
RPA4449 Republic Airlines 8 2026-05-16
RPA4352 - 8 2026-07-04
RPA4726 Republic Airlines 7 2026-07-25
RPA4493 Republic Airlines 7 2026-06-06
RPA4407 - 7 2026-07-06
RPA4643 Republic Airlines 6 2026-05-28
RPA4553 - 6 2026-07-02
RPA4747 Republic Airlines 5 2026-05-11
RPA4738 Republic Airlines 5 2026-05-13
RPA4664 - 5 2026-07-08
RPA4590 Republic Airlines 5 2026-04-15
RPA4562 - 5 2026-07-04
RPA4543 Republic Airlines 5 2026-06-30
RPA4515 - 5 2026-07-07
RPA4484 - 5 2026-07-02
RPA4807 - 4 2026-07-01

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RPA4706 BTV → DCA Jul 26, 18:00 UTCJul 26, 19:55 UTC1h 55m
2026-07-26 RPA4705 STL → PHL Jul 26, 14:45 UTCJul 26, 16:50 UTC2h 5m
2026-07-26 RPA4391 ALB → DCA Jul 26, 10:20 UTCJul 26, 12:30 UTC2h 10m
2026-07-26 RPA4403 GSO → LGA Jul 26, 02:00 UTCJul 26, 03:50 UTC1h 50m
2026-07-25 RPA4465 DCA → STL Jul 25, 23:30 UTCJul 26, 00:30 UTC1h 0m
2026-07-25 RPA4425 DCA → ALB Jul 25, 21:10 UTCJul 25, 22:10 UTC1h 0m
2026-07-25 RPA4386 DCA → DSM Jul 25, 17:00 UTCJul 25, 19:10 UTC2h 10m
2026-07-25 RPA4666 PIT → LGA Jul 25, 14:35 UTCJul 25, 15:40 UTC1h 5m
2026-07-25 RPA4666 PIT → LGA Jul 25, 14:34 UTCJul 25, 15:38 UTC1h 4m
2026-07-25 RPA4666 PIT → LGA Jul 25, 12:30 UTCJul 25, 13:40 UTC1h 10m
2026-07-25 RPA4806 PVD → DCA Jul 25, 10:20 UTCJul 25, 11:15 UTC55m
2026-07-25 RPA4662 LGA → RIC Jul 25, 04:20 UTCJul 25, 05:20 UTC1h 0m
2026-07-25 RPA4662 LGA → RIC Jul 25, 04:15 UTCJul 25, 05:15 UTC1h 0m
2026-07-25 RPA4726 STL → LGA Jul 25, 01:40 UTCJul 25, 03:30 UTC1h 50m
2026-07-24 RPA9928 BNA → IND Jul 24, 16:35 UTCJul 24, 17:30 UTC55m
2026-07-24 RPA4539 MEM → LGA Jul 24, 02:40 UTCJul 24, 03:40 UTC1h 0m
2026-07-23 RPA4457 DCA → RDU Jul 23, 23:30 UTCJul 24, 00:55 UTC1h 25m
2026-07-23 RPA4457 DCA → RDU Jul 23, 23:26 UTCJul 24, 00:50 UTC1h 24m
2026-07-23 RPA4647 RDU → LGA Jul 23, 21:10 UTCJul 23, 22:20 UTC1h 10m
2026-07-23 RPA4740 STL → LGA Jul 23, 17:40 UTCJul 23, 19:40 UTC2h 0m
2026-07-23 RPA4740 STL → LGA Jul 23, 17:36 UTCJul 23, 19:44 UTC2h 8m
2026-07-23 RPA4740 STL → LGA Jul 23, 14:35 UTCJul 23, 16:30 UTC1h 55m
2026-07-23 RPA4683 LGA → CHO Jul 23, 10:55 UTCJul 23, 12:50 UTC1h 55m
2026-07-23 RPA4589 LGA → ORF Jul 23, 01:05 UTCJul 23, 02:15 UTC1h 10m
2026-07-23 RPA4589 LGA → ORF Jul 23, 01:04 UTCJul 23, 02:24 UTC1h 20m
2026-07-22 RPA4437 MHT → DCA Jul 22, 21:55 UTCJul 22, 23:45 UTC1h 50m
2026-07-22 RPA4437 MHT → DCA Jul 22, 21:54 UTCJul 22, 23:44 UTC1h 50m
2026-07-22 RPA4600 LGA → IND Jul 22, 19:10 UTCJul 22, 20:55 UTC1h 45m
2026-07-22 RPA4343 BGR → LGA Jul 22, 16:25 UTCJul 22, 17:35 UTC1h 10m
2026-07-22 RPA4343 LGA → BGR Jul 22, 14:25 UTCJul 22, 15:25 UTC1h 0m
2026-07-22 RPA9928 BNA → IND Jul 22, 11:30 UTCJul 22, 13:15 UTC1h 45m
2026-07-17 RPA9947 - Jul 17, 13:40 UTCJul 17, 14:55 UTC1h 15m
2026-07-16 RPA9947 - Jul 16, 16:49 UTCJul 16, 19:10 UTC2h 20m
2026-07-15 RPA4724 - Jul 15, 21:50 UTCJul 15, 22:50 UTC1h 0m
2026-07-15 RPA4748 - Jul 15, 17:45 UTCJul 15, 19:50 UTC2h 5m
2026-07-15 RPA4748 - Jul 15, 14:55 UTCJul 15, 16:50 UTC1h 55m
2026-07-15 RPA4683 - Jul 15, 10:50 UTCJul 15, 12:25 UTC1h 35m
2026-07-15 RPA4510 - Jul 15, 00:40 UTCJul 15, 02:30 UTC1h 50m
2026-07-14 RPA4563 - Jul 14, 20:30 UTCJul 14, 22:10 UTC1h 40m
2026-07-14 RPA4563 RDU → ORD Jul 14, 20:29 UTCJul 14, 22:07 UTC1h 38m
2026-07-14 RPA4639 BNA → RDU Jul 14, 17:15 UTCJul 14, 18:30 UTC1h 15m
2026-07-14 RPA4344 - Jul 14, 14:25 UTCJul 14, 15:35 UTC1h 10m
2026-07-14 RPA4531 WSG → RDU Jul 14, 12:15 UTCJul 14, 13:10 UTC55m
2026-07-14 RPA4569 - Jul 14, 00:10 UTCJul 14, 01:10 UTC1h 0m
2026-07-14 RPA4569 ORD → PIT Jul 14, 00:06 UTCJul 14, 01:06 UTC1h 0m
2026-07-13 RPA4563 - Jul 13, 20:35 UTCJul 13, 22:10 UTC1h 35m
2026-07-13 RPA4563 RDU → ORD Jul 13, 20:33 UTCJul 13, 22:12 UTC1h 39m
2026-07-13 RPA4658 - Jul 13, 17:40 UTCJul 13, 18:50 UTC1h 10m
2026-07-13 RPA4476 - Jul 13, 14:45 UTCJul 13, 16:00 UTC1h 15m
2026-07-13 RPA4387 - Jul 13, 12:30 UTCJul 13, 13:40 UTC1h 10m

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 N417YX page for operator, model, and routing details .

Mode-S A4F05D frequently asked

What is Mode-S code A4F05D?
A4F05D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N417YX.
Where is Mode-S A4F05D registered?
Mode-S code A4F05D 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 A4F05D broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 19:55 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4F05D, octal 51170135, decimal 10,809,437.
What flights does A4F05D operate?
Mode-S A4F05D has broadcast 20 distinct callsigns, including RPA4666, RPA4774, RPA4757, RPA4561, RPA4449.