sensors Mode-S transponder

4081BD

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-TTSD · AIRBUS A-320neo

Hex
4081BD
Octal
20100675
Decimal
4,227,517
Country
GB
Tail
G-TTSD
Type
A20N
Transponder active on ground
Flights observed
226
Distinct callsigns
20
Country
GB
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 4081BD.

Country allocation

The ICAO 24-bit address 4081BD 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 20 distinct

Callsign Airline Flights Last seen
BAW523 British Airways 5 2026-05-21
BAW522 British Airways 5 2026-05-20
BAW521 British Airways 5 2026-05-22
BAW520R British Airways 5 2026-05-22
SHT4YL - 3 2026-04-27
SHT14G - 3 2026-04-28
BAW708 British Airways 3 2026-05-23
BAW6NL British Airways 3 2026-04-23
BAW564Y British Airways 3 2026-04-22
SHT9B - 2 2026-04-17
SHT5R - 2 2026-05-23
SHT5N - 2 2026-04-28
SHT4H - 2 2026-05-23
SHT15B - 2 2026-04-28
BAW94DL British Airways 2 2026-05-07
BAW82DM British Airways 2 2026-05-28
BAW825 British Airways 2 2026-05-28
BAW755 - 2 2026-04-13
BAW709 British Airways 2 2026-05-23
BAW707 British Airways 2 2026-05-28

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 BAW5RF FCO → LHR May 30, 14:40 UTCMay 30, 15:15 UTC35m
2026-05-30 BAW554R LHR → FCO May 30, 11:20 UTCMay 30, 13:10 UTC1h 50m
2026-05-30 BAW399 BRU → LHR May 30, 04:40 UTCMay 30, 09:20 UTC4h 40m
2026-05-29 BAW398 LHR → BRU May 29, 18:15 UTCMay 29, 22:25 UTC4h 10m
2026-05-29 SHT9C EDI → LHR May 29, 14:35 UTCMay 29, 15:30 UTC55m
2026-05-29 SHT8E LHR → EDI May 29, 12:35 UTCMay 29, 13:30 UTC55m
2026-05-29 BAW473D BCN → LHR May 29, 08:30 UTCMay 29, 10:35 UTC2h 5m
2026-05-29 BAW472M LHR → BCN May 29, 05:30 UTCMay 29, 07:15 UTC1h 45m
2026-05-28 BAW707 ZRH → LHR May 28, 16:50 UTCMay 28, 21:10 UTC4h 20m
2026-05-28 BAW706 LHR → VIE May 28, 11:20 UTCMay 28, 15:35 UTC4h 15m
2026-05-28 BAW825 PRG → LHR May 28, 08:25 UTCMay 28, 09:20 UTC55m
2026-05-28 BAW82DM LHR → DUB May 28, 05:30 UTCMay 28, 06:20 UTC50m
2026-05-27 BAW9GB GIB → LHR May 27, 18:40 UTCMay 27, 20:45 UTC2h 5m
2026-05-27 BAW8LX LHR → GIB May 27, 15:25 UTCMay 27, 17:20 UTC1h 55m
2026-05-27 BAW571 MXP → LHR May 27, 12:20 UTCMay 27, 13:50 UTC1h 30m
2026-05-27 BAW7RL LHR → LIN May 27, 09:10 UTCMay 27, 10:35 UTC1h 25m
2026-05-27 SHT15E - May 27, 06:09 UTCMay 27, 06:55 UTC45m
2026-05-26 SHT14P - May 26, 19:25 UTCMay 26, 20:00 UTC35m
2026-05-26 BAW645 KLX → LHR May 26, 13:54 UTCMay 26, 16:35 UTC2h 40m
2026-05-26 BAW644 HER → LHR May 26, 09:35 UTCMay 26, 12:14 UTC2h 40m
2026-05-26 BAW339 LHR → NCE May 26, 05:30 UTCMay 26, 07:15 UTC1h 45m
2026-05-25 BAW338 NCE → LHR May 25, 19:54 UTCMay 25, 21:24 UTC1h 30m
2026-05-25 BAW819K CPH → LHR May 25, 16:35 UTCMay 25, 18:05 UTC1h 30m
2026-05-25 BAW8TD LHR → CPH May 25, 14:05 UTCMay 25, 15:30 UTC1h 25m
2026-05-25 SHT9Z EDI → LHR May 25, 10:40 UTCMay 25, 11:50 UTC1h 10m
2026-05-25 SHT8G - May 25, 08:10 UTCMay 25, 09:05 UTC55m
2026-05-25 SHT9E EDI → LHR May 25, 05:35 UTCMay 25, 06:45 UTC1h 10m
2026-05-24 SHT8V LHR → EDI May 24, 20:15 UTCMay 24, 21:10 UTC55m
2026-05-24 BAW7PI OSL → LHR May 24, 17:30 UTCMay 24, 18:45 UTC1h 15m
2026-05-24 BAW762 LHR → OSL May 24, 15:15 UTCMay 24, 16:30 UTC1h 15m
2026-05-24 BAW501 LIS → LHR May 24, 10:55 UTCMay 24, 13:25 UTC2h 30m
2026-05-24 BAW50P LHR → LIS May 24, 06:35 UTCMay 24, 08:50 UTC2h 15m
2026-05-23 BAW709 ZRH → LHR May 23, 17:50 UTCMay 23, 22:05 UTC4h 15m
2026-05-23 BAW708 LHR → ZRH May 23, 12:00 UTCMay 23, 16:05 UTC4h 5m
2026-05-23 SHT5R - May 23, 08:55 UTCMay 23, 09:50 UTC55m
2026-05-23 SHT4H - May 23, 06:50 UTCMay 23, 07:45 UTC55m
2026-05-22 BAW603 PSA → LHR May 22, 18:00 UTCMay 22, 19:50 UTC1h 50m
2026-05-22 BAW602 LHR → PSA May 22, 14:55 UTCMay 22, 16:35 UTC1h 40m
2026-05-22 BAW521 FNC → LHR May 22, 11:35 UTCMay 22, 13:15 UTC1h 40m
2026-05-22 BAW520R LHR → FLR May 22, 07:55 UTCMay 22, 09:50 UTC1h 55m
2026-05-21 BAW397 BRU → LHR May 21, 09:10 UTCMay 21, 20:10 UTC11h 0m
2026-05-21 BAW523 PDL → LHR May 21, 05:20 UTCMay 21, 07:30 UTC2h 10m
2026-05-20 BAW522 LHR → PDL May 20, 18:30 UTCMay 20, 20:00 UTC1h 30m
2026-05-20 BAW481B BCN → LHR May 20, 15:05 UTCMay 20, 17:05 UTC2h 0m
2026-05-20 BAW480N LHR → BCN May 20, 11:50 UTCMay 20, 13:20 UTC1h 30m
2026-05-20 BAW813C CPH → LHR May 20, 08:35 UTCMay 20, 10:20 UTC1h 45m
2026-05-20 BAW812 LHR → CPH May 20, 05:40 UTCMay 20, 07:05 UTC1h 25m
2026-05-19 BAW709 ZRH → LHR May 19, 17:00 UTCMay 19, 21:30 UTC4h 30m
2026-05-19 BAW708 LHR → ZRH May 19, 13:30 UTCMay 19, 15:40 UTC2h 10m
2026-05-19 BAW708 LHR → ZRH May 19, 11:35 UTCMay 19, 13:25 UTC1h 50m

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-TTSD page for operator, model, and routing details .

Mode-S 4081BD frequently asked

What is Mode-S code 4081BD?
4081BD is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-TTSD.
Where is Mode-S 4081BD registered?
Mode-S code 4081BD 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 4081BD broadcasting right now?
Mode-S 4081BD is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4081BD, octal 20100675, decimal 4,227,517.
What flights does 4081BD operate?
Mode-S 4081BD has broadcast 20 distinct callsigns, including BAW523, BAW522, BAW521, BAW520R, SHT4YL.