sensors Mode-S transponder

43C61D

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to ZZ504 · Beech Shadow R1+

Hex
43C61D
Octal
20743035
Decimal
4,441,629
Country
GB
Tail
ZZ504
Type
B350
No current signal · last broadcast 3d ago
Flights observed
45
Distinct callsigns
14
Country
GB
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S 43C61D.

Country allocation

The ICAO 24-bit address 43C61D falls within the block assigned to United Kingdom (GB) by ICAO Annex 10, Volume III. Every aircraft registered in United Kingdom 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 14 distinct

Callsign Airline Flights Last seen
WAD54 - 9 2026-06-09
RFR7144 - 6 2026-05-28
SNAKE54 - 5 2026-05-29
SCARB54 - 5 2026-06-11
RFR7143 - 4 2026-05-27
MONTY54 - 4 2026-06-02
WIDGT54 - 3 2026-05-18
SRPNT54 - 2 2026-06-02
RFR7142 - 2 2026-05-26
VNTGE54 - 1 2026-06-04
SCRCR02 - 1 2026-05-12
SCRAB54 - 1 2026-05-14
KNIGT54 - 1 2026-06-01
KNGHT54 - 1 2026-06-02

Recent flights last 45

DateFlightRouteTakeoffLandingDuration
2026-06-11 SCARB54 - Jun 11, 08:55 UTCJun 11, 11:05 UTC2h 10m
2026-06-09 WAD54 - Jun 9, 13:50 UTCJun 9, 15:50 UTC2h 0m
2026-06-09 WAD54 - Jun 9, 09:40 UTCJun 9, 11:40 UTC2h 0m
2026-06-08 WAD54 - Jun 8, 14:50 UTCJun 8, 17:05 UTC2h 15m
2026-06-08 WAD54 - Jun 8, 10:05 UTCJun 8, 12:10 UTC2h 5m
2026-06-04 VNTGE54 WTN → WTN Jun 4, 11:10 UTCJun 4, 15:35 UTC4h 25m
2026-06-02 KNGHT54 - Jun 2, 19:55 UTCJun 3, 00:00 UTC4h 5m
2026-06-02 MONTY54 WTN → WTN Jun 2, 12:55 UTCJun 2, 16:20 UTC3h 25m
2026-06-02 SRPNT54 WTN → WTN Jun 2, 08:30 UTCJun 2, 11:20 UTC2h 50m
2026-06-01 SCARB54 WTN → WTN Jun 1, 13:35 UTCJun 1, 16:35 UTC3h 0m
2026-06-01 KNIGT54 WTN → WTN Jun 1, 08:55 UTCJun 1, 12:05 UTC3h 10m
2026-05-29 SNAKE54 - May 29, 09:55 UTCMay 29, 12:45 UTC2h 50m
2026-05-28 RFR7144 - May 28, 13:05 UTCMay 28, 16:20 UTC3h 15m
2026-05-28 RFR7144 WTN → PSA May 28, 08:00 UTCMay 28, 10:55 UTC2h 55m
2026-05-27 RFR7143 - May 27, 14:10 UTCMay 27, 17:15 UTC3h 5m
2026-05-27 RFR7143 WTN → RMS May 27, 09:00 UTCMay 27, 10:45 UTC1h 45m
2026-05-26 RFR7142 NCE → WTN May 26, 13:50 UTCMay 26, 16:30 UTC2h 40m
2026-05-26 RFR7142 - May 26, 08:15 UTCMay 26, 11:09 UTC2h 55m
2026-05-22 SRPNT54 - May 22, 08:55 UTCMay 22, 11:35 UTC2h 40m
2026-05-21 WAD54 - May 21, 15:55 UTCMay 21, 16:35 UTC40m
2026-05-21 WAD54 - May 21, 14:15 UTCMay 21, 15:00 UTC45m
2026-05-21 WAD54 WTN → JER May 21, 09:00 UTCMay 21, 11:40 UTC2h 40m
2026-05-20 WAD54 - May 20, 15:25 UTCMay 20, 16:50 UTC1h 25m
2026-05-20 WAD54 - May 20, 08:25 UTCMay 20, 11:10 UTC2h 45m
2026-05-19 SNAKE54 - May 19, 14:30 UTCMay 19, 16:05 UTC1h 35m
2026-05-19 SNAKE54 - May 19, 13:00 UTCMay 19, 14:05 UTC1h 5m
2026-05-19 SCARB54 - May 19, 09:10 UTCMay 19, 11:25 UTC2h 15m
2026-05-18 WIDGT54 WTN → WTN May 18, 12:55 UTCMay 18, 16:15 UTC3h 20m
2026-05-18 SNAKE54 WTN → WTN May 18, 08:25 UTCMay 18, 11:25 UTC3h 0m
2026-05-15 WIDGT54 - May 15, 08:35 UTCMay 15, 11:05 UTC2h 30m
2026-05-14 SCRAB54 WTN → WTN May 14, 14:20 UTCMay 14, 16:25 UTC2h 5m
2026-05-14 WIDGT54 WTN → WTN May 14, 09:10 UTCMay 14, 11:20 UTC2h 10m
2026-05-13 SCARB54 WTN → WTN May 13, 09:30 UTCMay 13, 12:20 UTC2h 50m
2026-05-12 SCRCR02 - May 12, 15:01 UTCMay 12, 15:25 UTC25m
2026-05-12 MONTY54 WTN → WTN May 12, 11:40 UTCMay 12, 12:05 UTC25m
2026-05-12 MONTY54 - May 12, 10:00 UTCMay 12, 11:35 UTC1h 35m
2026-05-11 MONTY54 - May 11, 13:10 UTCMay 11, 16:50 UTC3h 40m
2026-05-08 SNAKE54 - May 8, 09:49 UTCMay 8, 12:00 UTC2h 10m
2026-05-05 SCARB54 - May 5, 14:45 UTCMay 5, 17:00 UTC2h 15m
2026-04-30 RFR7143 - Apr 30, 14:20 UTCApr 30, 17:55 UTC3h 35m
2026-04-30 RFR7143 - Apr 30, 08:15 UTCApr 30, 12:10 UTC3h 55m
2026-04-27 RFR7144 AKT → AKT Apr 27, 13:05 UTCApr 27, 15:15 UTC2h 10m
2026-04-27 RFR7144 AKT → AKT Apr 27, 10:20 UTCApr 27, 12:45 UTC2h 25m
2026-04-23 RFR7144 - Apr 23, 11:15 UTCApr 23, 16:35 UTC5h 20m
2026-04-21 RFR7144 - Apr 21, 12:15 UTCApr 21, 17:10 UTC4h 55m

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 ZZ504 page for operator, model, and routing details .

Mode-S 43C61D frequently asked

What is Mode-S code 43C61D?
43C61D is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to ZZ504.
Where is Mode-S 43C61D registered?
Mode-S code 43C61D is allocated to United Kingdom (GB). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 43C61D broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 43C61D, octal 20743035, decimal 4,441,629.
What flights does 43C61D operate?
Mode-S 43C61D has broadcast 14 distinct callsigns, including WAD54, RFR7144, SNAKE54, SCARB54, RFR7143.