sensors Mode-S transponder

400EC8

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-BYUD · GROB G-115

Hex
400EC8
Octal
20007310
Decimal
4,198,088
Country
GB
Tail
G-BYUD
Type
G115
No current signal · last broadcast 15h ago
Flights observed
61
Distinct callsigns
18
Country
GB
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S 400EC8.

Country allocation

The ICAO 24-bit address 400EC8 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 18 distinct

Callsign Airline Flights Last seen
UAQ04 - 12 2026-07-17
UAQ02 - 9 2026-07-15
UAQ11 - 7 2026-05-21
UAX68 - 4 2026-07-09
UAX62 - 4 2026-05-01
UAX61 - 4 2026-05-22
UAQ21 - 4 2026-06-19
UAQ01 - 4 2026-07-16
UAX65 - 3 2026-06-23
UAQ023 - 2 2026-06-02
UAX71 - 1 2026-07-10
UAX63 - 1 2026-04-17
UAX25 - 1 2026-04-23
UAQ816 - 1 2026-04-23
UAQ23 - 1 2026-04-22
UAQ06 - 1 2026-04-27
UAQ007 - 1 2026-04-24
STEELER2 - 1 2026-05-01

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-17 UAQ04 - Jul 17, 09:45 UTCJul 17, 10:50 UTC1h 5m
2026-07-16 UAQ01 - Jul 16, 13:34 UTCJul 16, 14:35 UTC1h 0m
2026-07-16 UAQ01 - Jul 16, 10:04 UTCJul 16, 10:50 UTC45m
2026-07-15 UAQ02 - Jul 15, 11:05 UTCJul 15, 12:10 UTC1h 5m
2026-07-14 UAQ01 - Jul 14, 09:10 UTCJul 14, 10:05 UTC55m
2026-07-10 UAX71 - Jul 10, 09:10 UTCJul 10, 10:15 UTC1h 5m
2026-07-09 UAX68 - Jul 9, 11:25 UTCJul 9, 12:20 UTC55m
2026-07-08 UAQ04 - Jul 8, 12:05 UTCJul 8, 12:40 UTC35m
2026-07-08 UAX68 - Jul 8, 10:05 UTCJul 8, 11:20 UTC1h 15m
2026-06-29 UAX68 - Jun 29, 11:50 UTCJun 29, 13:04 UTC1h 15m
2026-06-26 UAX68 - Jun 26, 09:00 UTCJun 26, 09:30 UTC30m
2026-06-23 UAX65 - Jun 23, 12:35 UTCJun 23, 13:09 UTC35m
2026-06-23 UAX65 - Jun 23, 09:24 UTCJun 23, 11:14 UTC1h 50m
2026-06-22 UAQ04 - Jun 22, 13:54 UTCJun 22, 14:34 UTC40m
2026-06-22 UAQ04 - Jun 22, 12:25 UTCJun 22, 12:54 UTC30m
2026-06-22 UAQ02 - Jun 22, 11:09 UTCJun 22, 11:54 UTC45m
2026-06-22 UAQ04 - Jun 22, 08:35 UTCJun 22, 09:34 UTC1h 0m
2026-06-19 UAQ21 - Jun 19, 11:45 UTCJun 19, 13:29 UTC1h 45m
2026-06-19 UAQ21 - Jun 19, 09:34 UTCJun 19, 10:44 UTC1h 10m
2026-06-19 UAQ21 - Jun 19, 08:50 UTCJun 19, 09:09 UTC20m
2026-06-18 UAQ02 - Jun 18, 13:15 UTCJun 18, 14:15 UTC1h 0m
2026-06-18 UAQ01 - Jun 18, 10:25 UTCJun 18, 11:30 UTC1h 5m
2026-06-17 UAQ02 - Jun 17, 09:35 UTCJun 17, 10:50 UTC1h 15m
2026-06-16 UAQ04 - Jun 16, 14:30 UTCJun 16, 15:09 UTC40m
2026-06-16 UAQ04 - Jun 16, 12:25 UTCJun 16, 13:09 UTC45m
2026-06-16 UAQ04 - Jun 16, 09:20 UTCJun 16, 10:09 UTC50m
2026-06-02 UAQ023 - Jun 2, 12:15 UTCJun 2, 13:20 UTC1h 5m
2026-06-02 UAQ023 - Jun 2, 09:20 UTCJun 2, 11:20 UTC2h 0m
2026-05-22 UAX61 - May 22, 09:25 UTCMay 22, 10:25 UTC1h 0m
2026-05-21 UAQ11 - May 21, 12:45 UTCMay 21, 14:15 UTC1h 30m
2026-05-21 UAQ11 - May 21, 10:15 UTCMay 21, 11:30 UTC1h 15m
2026-05-19 UAQ04 - May 19, 09:30 UTCMay 19, 10:35 UTC1h 5m
2026-05-11 UAQ04 - May 11, 12:50 UTCMay 11, 13:50 UTC1h 0m
2026-05-11 UAQ04 - May 11, 09:50 UTCMay 11, 11:00 UTC1h 10m
2026-05-08 UAX61 - May 8, 10:44 UTCMay 8, 11:49 UTC1h 5m
2026-05-07 UAX61 - May 7, 14:30 UTCMay 7, 15:30 UTC1h 0m
2026-05-06 UAX61 - May 6, 13:20 UTCMay 6, 14:20 UTC1h 0m
2026-05-01 STEELER2 - May 1, 13:20 UTCMay 1, 14:20 UTC1h 0m
2026-05-01 UAX62 - May 1, 09:55 UTCMay 1, 11:00 UTC1h 5m
2026-04-30 UAQ21 - Apr 30, 12:50 UTCApr 30, 14:30 UTC1h 40m
2026-04-29 UAQ02 - Apr 29, 14:45 UTCApr 29, 15:50 UTC1h 5m
2026-04-29 UAQ11 - Apr 29, 12:45 UTCApr 29, 13:50 UTC1h 5m
2026-04-28 UAX65 - Apr 28, 12:55 UTCApr 28, 14:00 UTC1h 5m
2026-04-27 UAQ06 - Apr 27, 12:45 UTCApr 27, 14:30 UTC1h 45m
2026-04-24 UAQ007 - Apr 24, 13:00 UTCApr 24, 14:55 UTC1h 55m
2026-04-23 UAQ816 - Apr 23, 13:55 UTCApr 23, 15:00 UTC1h 5m
2026-04-23 UAX62 - Apr 23, 12:05 UTCApr 23, 13:15 UTC1h 10m
2026-04-23 UAX25 - Apr 23, 10:30 UTCApr 23, 11:25 UTC55m
2026-04-22 UAQ23 - Apr 22, 10:50 UTCApr 22, 12:30 UTC1h 40m
2026-04-21 UAQ02 - Apr 21, 13:35 UTCApr 21, 14:45 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 G-BYUD page for operator, model, and routing details .

Mode-S 400EC8 frequently asked

What is Mode-S code 400EC8?
400EC8 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-BYUD.
Where is Mode-S 400EC8 registered?
Mode-S code 400EC8 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 400EC8 broadcasting right now?
No active broadcast right now. Last signal was 15h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 400EC8, octal 20007310, decimal 4,198,088.
What flights does 400EC8 operate?
Mode-S 400EC8 has broadcast 18 distinct callsigns, including UAQ04, UAQ02, UAQ11, UAX68, UAX62.