sensors Mode-S transponder

4003A6

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to VQ-TBB · ATR-42-500

Hex
4003A6
Octal
20001646
Decimal
4,195,238
Country
GB
Tail
VQ-TBB
Type
AT45
No current signal · last broadcast 22d ago
Flights observed
25
Distinct callsigns
18
Country
GB
Last broadcast
22d ago

Last known position

Most recent position reported by Mode-S 4003A6.

Country allocation

The ICAO 24-bit address 4003A6 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

Recent flights last 25

DateFlightRouteTakeoffLandingDuration
2026-05-07 IWY411 SDQ → EIS May 7, 21:30 UTCMay 7, 21:50 UTC20m
2026-05-02 IWY410 EIS → SDQ May 2, 17:00 UTCMay 2, 17:30 UTC30m
2026-04-30 IWY768 BGI → DOM Apr 30, 22:50 UTCApr 30, 23:10 UTC20m
2026-04-29 IWY713 DOM → BGI Apr 29, 17:50 UTCApr 29, 18:20 UTC30m
2026-04-29 IWY712 BGI → DOM Apr 29, 15:55 UTCApr 29, 16:20 UTC25m
2026-04-23 IWY741 DOM → BGI Apr 23, 21:05 UTCApr 23, 21:25 UTC20m
2026-04-23 IWY740 BGI → DOM Apr 23, 18:45 UTCApr 23, 19:10 UTC25m
2026-04-23 IWY787 - Apr 23, 13:45 UTCApr 23, 13:55 UTC10m
2026-04-22 IWY788 BGI → OGL Apr 22, 22:05 UTCApr 22, 22:30 UTC25m
2026-04-22 IWY557 EIS → BGI Apr 22, 20:10 UTCApr 22, 20:25 UTC15m
2026-04-22 IWY556 SXM → EIS Apr 22, 15:15 UTCApr 22, 15:30 UTC15m
2026-04-21 IWY764 SVD → GND Apr 21, 23:35 UTCApr 22, 00:00 UTC25m
2026-04-21 IWY764 SVD → GND Apr 21, 22:35 UTCApr 21, 23:00 UTC25m
2026-04-21 IWY741 DOM → BGI Apr 21, 21:10 UTCApr 21, 21:20 UTC10m
2026-04-21 IWY740 BGI → DOM Apr 21, 19:15 UTCApr 21, 19:30 UTC15m
2026-04-19 IWY713 DOM → BGI Apr 19, 16:45 UTCApr 19, 16:55 UTC10m
2026-04-19 IWY712 - Apr 19, 14:50 UTCApr 19, 15:05 UTC15m
2026-04-14 IWY703 - Apr 14, 13:20 UTCApr 14, 13:50 UTC30m
2026-04-13 IWY784 - Apr 13, 23:20 UTCApr 13, 23:35 UTC15m
2026-04-13 IWY783 - Apr 13, 19:45 UTCApr 13, 20:05 UTC20m
2026-04-13 IWY715 - Apr 13, 17:55 UTCApr 13, 18:25 UTC30m
2026-04-13 IWY2703 - Apr 13, 16:55 UTCApr 13, 17:15 UTC20m
2026-04-13 IWY764 - Apr 13, 02:00 UTCApr 13, 02:15 UTC15m
2026-04-13 IWY764 - Apr 13, 01:00 UTCApr 13, 01:25 UTC25m
2026-04-12 IWY743 - Apr 12, 23:55 UTCApr 13, 00:05 UTC10m

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 VQ-TBB page for operator, model, and routing details .

Mode-S 4003A6 frequently asked

What is Mode-S code 4003A6?
4003A6 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to VQ-TBB.
Where is Mode-S 4003A6 registered?
Mode-S code 4003A6 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 4003A6 broadcasting right now?
No active broadcast right now. Last signal was 22d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4003A6, octal 20001646, decimal 4,195,238.
What flights does 4003A6 operate?
Mode-S 4003A6 has broadcast 18 distinct callsigns, including IWY764, IWY741, IWY740, IWY713, IWY712.