sensors Mode-S transponder

4081A3

ICAO 24-bit transponder address · allocated to United Kingdom

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

Hex
4081A3
Octal
20100643
Decimal
4,227,491
Country
GB
Tail
G-TTSC
Type
A20N
No current signal · last broadcast 15h ago
Flights observed
17
Distinct callsigns
9
Country
GB
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S 4081A3.

Country allocation

The ICAO 24-bit address 4081A3 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 9 distinct

Callsign Airline Flights Last seen
BAW891 - 5 2026-04-13
BAW330U - 3 2026-04-13
SHT9W - 2 2026-04-14
SHT8B - 2 2026-04-14
BAW890 - 1 2026-04-13
BAW73NA British Airways 1 2026-04-13
BAW739 - 1 2026-04-13
BAW479 - 1 2026-04-12
BAW331 - 1 2026-04-13

Recent flights last 17

DateFlightRouteTakeoffLandingDuration
2026-04-14 SHT9W - Apr 14, 09:10 UTCApr 14, 09:20 UTC10m
2026-04-14 SHT9W - Apr 14, 08:25 UTCApr 14, 09:05 UTC40m
2026-04-14 SHT8B - Apr 14, 07:10 UTCApr 14, 07:25 UTC15m
2026-04-14 SHT8B - Apr 14, 06:25 UTCApr 14, 07:10 UTC45m
2026-04-13 BAW739 ZRH → LHR Apr 13, 20:10 UTCApr 13, 21:20 UTC1h 10m
2026-04-13 BAW73NA LHR → GVA Apr 13, 17:25 UTCApr 13, 18:40 UTC1h 15m
2026-04-13 BAW331 - Apr 13, 14:05 UTCApr 13, 15:30 UTC1h 25m
2026-04-13 BAW330U - Apr 13, 12:20 UTCApr 13, 12:40 UTC20m
2026-04-13 BAW330U - Apr 13, 11:55 UTCApr 13, 12:40 UTC45m
2026-04-13 BAW330U - Apr 13, 11:00 UTCApr 13, 12:15 UTC1h 15m
2026-04-13 BAW891 - Apr 13, 08:20 UTCApr 13, 08:45 UTC25m
2026-04-13 BAW891 - Apr 13, 07:55 UTCApr 13, 08:45 UTC50m
2026-04-13 BAW891 - Apr 13, 04:20 UTCApr 13, 08:15 UTC3h 55m
2026-04-13 BAW891 - Apr 13, 03:55 UTCApr 13, 07:50 UTC3h 55m
2026-04-13 BAW891 TBS → VAS Apr 13, 03:20 UTCApr 13, 04:15 UTC55m
2026-04-13 BAW890 - Apr 13, 00:45 UTCApr 13, 01:15 UTC30m
2026-04-12 BAW479 - Apr 12, 17:15 UTCApr 12, 18:40 UTC1h 25m

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

Mode-S 4081A3 frequently asked

What is Mode-S code 4081A3?
4081A3 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-TTSC.
Where is Mode-S 4081A3 registered?
Mode-S code 4081A3 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 4081A3 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 4081A3, octal 20100643, decimal 4,227,491.
What flights does 4081A3 operate?
Mode-S 4081A3 has broadcast 9 distinct callsigns, including BAW891, BAW330U, SHT9W, SHT8B, BAW890.