Apparatus

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sensors Mode-S transponder

405BFC

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-YMMS · BOEING 777-200

Hex
405BFC
Octal
20055774
Decimal
4,217,852
Country
GB
Tail
G-YMMS
Type
B772
Broadcasting now · callsign BAW142 · 38,000 ft
Flights observed
103
Distinct callsigns
20
Country
GB
Last broadcast
41m ago

Current position

405BFC is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 405BFC 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
BAW134 British Airways 12 2026-05-06
BAW138 British Airways 10 2026-04-16
BAW143 British Airways 7 2026-05-29
BAW249 British Airways 6 2026-05-15
BAW248 British Airways 6 2026-05-15
BAW198 British Airways 6 2026-05-24
BAW139 British Airways 6 2026-04-15
BAW88C British Airways 5 2026-05-06
BAW5VY British Airways 5 2026-05-05
BAW142 British Airways 5 2026-05-29
BAW135 British Airways 5 2026-04-17
BAW199 British Airways 4 2026-05-23
BAW46EZ British Airways 2 2026-05-14
BAW461 British Airways 2 2026-05-14
BAW2LJ British Airways 2 2026-05-20
BAW257 British Airways 2 2026-04-27
BAW256 British Airways 2 2026-04-28
BAW22B British Airways 2 2026-05-19
BAW97A British Airways 1 2026-05-21
BAW9175 British Airways 1 2026-05-28

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 BAW142 DEL → LHR May 29, 21:10 UTCMay 30, 05:00 UTC7h 50m
2026-05-29 BAW143 LHR → DEL May 29, 11:00 UTCMay 29, 18:50 UTC7h 50m
2026-05-28 BAW9175 CWL → LHR May 28, 21:30 UTCMay 28, 21:45 UTC15m
2026-05-24 BAW9171 CWL → BOS May 24, 20:30 UTCMay 24, 20:45 UTC15m
2026-05-24 BAW198 BOM → LHR May 24, 08:05 UTCMay 24, 17:35 UTC9h 30m
2026-05-23 BAW199 LHR → BOM May 23, 20:25 UTCMay 24, 05:05 UTC8h 40m
2026-05-23 BAW198 BOM → LHR May 23, 07:55 UTCMay 23, 17:40 UTC9h 45m
2026-05-22 BAW199 LHR → BOM May 22, 20:35 UTCMay 23, 05:15 UTC8h 39m
2026-05-22 BAW196E IAH → LHR May 22, 03:10 UTCMay 22, 11:15 UTC8h 5m
2026-05-21 BAW97A LHR → IAH May 21, 14:25 UTCMay 22, 00:35 UTC10h 10m
2026-05-21 BAW290 LHR → IAD May 21, 02:20 UTCMay 21, 09:00 UTC6h 40m
2026-05-20 BAW291 LHR → SFO May 20, 14:35 UTCMay 20, 22:30 UTC7h 55m
2026-05-20 BAW2LJ BWI → LHR May 20, 02:15 UTCMay 20, 09:05 UTC6h 51m
2026-05-19 BAW22B LHR → BWI May 19, 16:00 UTCMay 19, 23:40 UTC7h 40m
2026-05-19 BAW264 IAD → LHR May 19, 00:10 UTCMay 19, 09:50 UTC9h 40m
2026-05-18 BAW265 LHR → SAN May 18, 11:10 UTCMay 18, 21:55 UTC10h 44m
2026-05-18 BAW298 ORD → LHR May 18, 01:00 UTCMay 18, 08:20 UTC7h 20m
2026-05-17 BAW299 LHR → ORD May 17, 12:40 UTCMay 17, 20:55 UTC8h 15m
2026-05-17 BAW120 CVG → LHR May 17, 01:35 UTCMay 17, 08:45 UTC7h 10m
2026-05-16 BAW21V LHR → CVG May 16, 14:55 UTCMay 16, 23:10 UTC8h 15m
2026-05-15 BAW248 GIG → LHR May 15, 20:10 UTCMay 16, 06:41 UTC10h 31m
2026-05-15 BAW248 GIG → LHR May 15, 15:30 UTCMay 15, 18:05 UTC2h 35m
2026-05-15 BAW249 LHR → GIG May 15, 10:55 UTCMay 15, 13:45 UTC2h 50m
2026-05-14 BAW249 LHR → GIG May 14, 22:40 UTCMay 15, 09:25 UTC10h 45m
2026-05-14 BAW461 MAD → LHR May 14, 15:55 UTCMay 14, 18:35 UTC2h 40m
2026-05-14 BAW46EZ LHR → MAD May 14, 12:30 UTCMay 14, 14:05 UTC1h 35m
2026-05-08 BAW248 GIG → LHR May 8, 20:05 UTCMay 9, 06:55 UTC10h 50m
2026-05-08 BAW248 GIG → LHR May 8, 15:35 UTCMay 8, 18:15 UTC2h 40m
2026-05-08 BAW249 LHR → GIG May 8, 10:29 UTCMay 8, 13:15 UTC2h 45m
2026-05-07 BAW249 LHR → GIG May 7, 21:05 UTCMay 8, 08:24 UTC11h 20m
2026-05-06 BAW134 BOM → LHR May 6, 19:05 UTCMay 7, 13:55 UTC18h 50m
2026-05-06 BAW134 BOM → LHR May 6, 17:05 UTCMay 7, 13:55 UTC20h 50m
2026-05-06 BAW88C YVR → LHR May 6, 04:15 UTCMay 6, 13:05 UTC8h 50m
2026-05-05 BAW5VY LHR → YVR May 5, 16:50 UTCMay 6, 02:01 UTC9h 10m
2026-05-05 BAW88C YVR → LHR May 5, 04:30 UTCMay 5, 13:20 UTC8h 50m
2026-05-04 BAW5VY LHR → YVR May 4, 17:10 UTCMay 5, 02:10 UTC9h 1m
2026-05-04 BAW6AC ORD → LHR May 4, 02:35 UTCMay 4, 10:05 UTC7h 30m
2026-05-03 BAW7CP LHR → ORD May 3, 14:50 UTCMay 3, 22:45 UTC7h 55m
2026-05-02 BAW142 DEL → LHR May 2, 20:45 UTCMay 3, 05:35 UTC8h 49m
2026-05-02 BAW143 LHR → DEL May 2, 10:20 UTCMay 2, 18:20 UTC8h 0m
2026-05-01 BAW142 DEL → LHR May 1, 20:35 UTCMay 2, 05:35 UTC9h 1m
2026-05-01 BAW143 LHR → DEL May 1, 10:05 UTCMay 1, 18:10 UTC8h 5m
2026-04-30 BAW198 BOM → LHR Apr 30, 07:40 UTCApr 30, 17:55 UTC10h 15m
2026-04-30 BAW199 LHR → BOM Apr 30, 04:40 UTCApr 30, 04:55 UTC15m
2026-04-29 BAW199 LHR → BOM Apr 29, 20:20 UTCApr 30, 03:50 UTC7h 29m
2026-04-29 BAW461 MAD → LHR Apr 29, 16:05 UTCApr 29, 18:00 UTC1h 55m
2026-04-29 BAW46EZ LHR → MAD Apr 29, 12:15 UTCApr 29, 14:15 UTC2h 0m
2026-04-28 BAW256 DEL → LHR Apr 28, 04:55 UTCApr 28, 14:05 UTC9h 10m
2026-04-27 BAW257 LHR → DEL Apr 27, 18:20 UTCApr 28, 02:05 UTC7h 45m
2026-04-26 BAW134 BOM → LHR Apr 26, 19:05 UTCApr 27, 14:00 UTC18h 55m

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

Mode-S 405BFC frequently asked

What is Mode-S code 405BFC?
405BFC is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-YMMS.
Where is Mode-S 405BFC registered?
Mode-S code 405BFC 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 405BFC broadcasting right now?
Yes. Mode-S 405BFC is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 405BFC, octal 20055774, decimal 4,217,852.
What flights does 405BFC operate?
Mode-S 405BFC has broadcast 20 distinct callsigns, including BAW134, BAW138, BAW143, BAW249, BAW248.