sensors Mode-S transponder

40668C

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-WPDB · AIRBUS HELICOPTERS EC-135/635

Hex
40668C
Octal
20063214
Decimal
4,220,556
Country
GB
Tail
G-WPDB
Type
EC35
No current signal · last broadcast 20h ago
Flights observed
167
Distinct callsigns
3
Country
GB
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S 40668C.

Country allocation

The ICAO 24-bit address 40668C 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 3 distinct

Callsign Airline Flights Last seen
GWPDB - 163 2026-07-13
EZY52TN - 1 2026-05-08
EZY52RV - 1 2026-05-06

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 GWPDB - Jul 13, 14:35 UTCJul 13, 15:20 UTC45m
2026-07-13 GWPDB - Jul 13, 09:00 UTCJul 13, 09:45 UTC45m
2026-07-11 GWPDB - Jul 11, 11:55 UTCJul 11, 14:45 UTC2h 50m
2026-07-11 GWPDB - Jul 11, 08:15 UTCJul 11, 10:50 UTC2h 35m
2026-07-10 GWPDB BRS → BRS Jul 10, 12:10 UTCJul 10, 14:00 UTC1h 50m
2026-07-09 GWPDB - Jul 9, 11:25 UTCJul 9, 11:35 UTC10m
2026-07-09 GWPDB - Jul 9, 08:35 UTCJul 9, 08:55 UTC20m
2026-07-08 GWPDB - Jul 8, 12:55 UTCJul 8, 13:30 UTC35m
2026-07-08 GWPDB - Jul 8, 07:35 UTCJul 8, 08:05 UTC30m
2026-07-07 GWPDB - Jul 7, 14:25 UTCJul 7, 14:55 UTC30m
2026-07-07 GWPDB - Jul 7, 09:20 UTCJul 7, 09:50 UTC30m
2026-07-06 GWPDB GLO → BRS Jul 6, 13:05 UTCJul 6, 14:45 UTC1h 40m
2026-07-06 GWPDB - Jul 6, 11:20 UTCJul 6, 11:45 UTC25m
2026-07-06 GWPDB - Jul 6, 10:25 UTCJul 6, 10:35 UTC10m
2026-07-06 GWPDB - Jul 6, 09:10 UTCJul 6, 09:50 UTC40m
2026-07-03 GWPDB - Jul 3, 12:30 UTCJul 3, 13:20 UTC50m
2026-07-03 GWPDB - Jul 3, 10:15 UTCJul 3, 12:00 UTC1h 45m
2026-07-03 GWPDB - Jul 3, 08:50 UTCJul 3, 09:05 UTC15m
2026-07-03 GWPDB - Jul 3, 07:10 UTCJul 3, 08:00 UTC50m
2026-07-02 GWPDB - Jul 2, 13:10 UTCJul 2, 15:00 UTC1h 50m
2026-07-02 GWPDB - Jul 2, 12:00 UTCJul 2, 12:50 UTC50m
2026-07-02 GWPDB - Jul 2, 08:30 UTCJul 2, 10:05 UTC1h 35m
2026-07-01 GWPDB - Jul 1, 12:10 UTCJul 1, 13:25 UTC1h 15m
2026-07-01 GWPDB - Jul 1, 11:10 UTCJul 1, 11:20 UTC10m
2026-07-01 GWPDB - Jul 1, 09:20 UTCJul 1, 09:50 UTC30m
2026-07-01 GWPDB - Jul 1, 07:20 UTCJul 1, 07:50 UTC30m
2026-06-30 GWPDB - Jun 30, 13:45 UTCJun 30, 15:25 UTC1h 40m
2026-06-30 GWPDB - Jun 30, 08:00 UTCJun 30, 08:55 UTC55m
2026-06-29 GWPDB - Jun 29, 16:35 UTCJun 29, 16:59 UTC25m
2026-06-29 GWPDB - Jun 29, 15:34 UTCJun 29, 16:00 UTC25m
2026-06-29 GWPDB - Jun 29, 14:25 UTCJun 29, 14:39 UTC15m
2026-06-29 GWPDB - Jun 29, 09:20 UTCJun 29, 11:25 UTC2h 5m
2026-06-26 GWPDB - Jun 26, 19:09 UTCJun 26, 19:24 UTC15m
2026-06-26 GWPDB - Jun 26, 17:35 UTCJun 26, 18:04 UTC30m
2026-06-26 GWPDB - Jun 26, 11:14 UTCJun 26, 11:45 UTC30m
2026-06-26 GWPDB - Jun 26, 07:05 UTCJun 26, 08:05 UTC1h 0m
2026-06-25 GWPDB - Jun 25, 14:44 UTCJun 25, 15:04 UTC20m
2026-06-25 GWPDB - Jun 25, 11:50 UTCJun 25, 14:04 UTC2h 15m
2026-06-25 GWPDB - Jun 25, 06:35 UTCJun 25, 10:25 UTC3h 50m
2026-06-24 GWPDB - Jun 24, 11:20 UTCJun 24, 12:50 UTC1h 30m
2026-06-24 GWPDB - Jun 24, 10:30 UTCJun 24, 10:49 UTC20m
2026-06-24 GWPDB BRS → GLO Jun 24, 06:55 UTCJun 24, 09:19 UTC2h 25m
2026-06-23 GWPDB - Jun 23, 13:09 UTCJun 23, 13:55 UTC45m
2026-06-23 GWPDB - Jun 23, 08:09 UTCJun 23, 08:59 UTC50m
2026-06-22 GWPDB - Jun 22, 14:10 UTCJun 22, 14:49 UTC40m
2026-06-22 GWPDB - Jun 22, 12:30 UTCJun 22, 13:14 UTC45m
2026-06-22 - - Jun 22, 10:55 UTCJun 22, 11:09 UTC15m
2026-06-22 GWPDB - Jun 22, 09:00 UTCJun 22, 10:00 UTC1h 0m
2026-06-19 GWPDB - Jun 19, 13:34 UTCJun 19, 13:44 UTC10m
2026-06-19 GWPDB - Jun 19, 08:34 UTCJun 19, 09:14 UTC40m

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 G-WPDB page for operator, model, and routing details .

Mode-S 40668C frequently asked

What is Mode-S code 40668C?
40668C is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-WPDB.
Where is Mode-S 40668C registered?
Mode-S code 40668C 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 40668C broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 40668C, octal 20063214, decimal 4,220,556.
What flights does 40668C operate?
Mode-S 40668C has broadcast 3 distinct callsigns, including GWPDB, EZY52TN, EZY52RV.