sensors Mode-S transponder

4066B9

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-GDFF · BOEING 737-800

Hex
4066B9
Octal
20063271
Decimal
4,220,601
Country
GB
Tail
G-GDFF
Type
B738
Broadcasting now · callsign EXS68PV · 34,175 ft
Flights observed
342
Distinct callsigns
20
Country
GB
Last broadcast
Jul 26, 22:15 UTC

Current position

4066B9 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4066B9 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
EXS406R - 11 2026-07-12
EXS31DR - 10 2026-06-27
EXS19G - 10 2026-07-12
EXS42UD Jet2.com 8 2026-07-25
EXS27KL Jet2.com 8 2026-07-25
EXS66KE - 7 2026-06-27
EXS85NQ - 6 2026-07-15
EXS81TB Jet2.com 6 2026-06-27
EXS41M - 6 2026-07-15
EXS1418 Jet2.com 6 2026-06-27
EXS9AN - 4 2026-07-13
EXS96BL - 4 2026-07-13
EXS88J - 4 2026-06-23
EXS78LQ Jet2.com 4 2026-04-20
EXS76MK - 4 2026-07-13
EXS52P - 4 2026-07-13
EXS4N Jet2.com 4 2026-04-20
EXS45NG Jet2.com 4 2026-04-19
EXS409M - 4 2026-07-15
EXS1MA - 4 2026-06-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 EXS8VB BRS → JTR Jul 26, 19:20 UTCJul 26, 22:15 UTC2h 55m
2026-07-26 EXS19WU TIV → STN Jul 26, 14:30 UTCJul 26, 17:05 UTC2h 35m
2026-07-26 EXS84NE STN → CMF Jul 26, 09:20 UTCJul 26, 12:40 UTC3h 20m
2026-07-26 EXS83JH STN → STN Jul 26, 05:25 UTCJul 26, 08:15 UTC2h 51m
2026-07-25 EXS32TE BRS → JSI Jul 25, 17:30 UTCJul 26, 01:50 UTC8h 20m
2026-07-25 EXS42UD STN → PMI Jul 25, 13:40 UTCJul 25, 16:00 UTC2h 20m
2026-07-25 EXS27KL LCA → STN Jul 25, 10:10 UTCJul 25, 12:25 UTC2h 15m
2026-07-25 EXS047A MAN → LBA Jul 25, 08:10 UTCJul 25, 08:45 UTC35m
2026-07-24 EXS8UM FCO → MAN Jul 24, 20:30 UTCJul 24, 23:30 UTC3h 0m
2026-07-24 EXS48TR PMI → BRS Jul 24, 16:05 UTCJul 24, 18:55 UTC2h 50m
2026-07-24 EXS87RD ACE → BRS Jul 24, 11:00 UTCJul 24, 14:20 UTC3h 20m
2026-07-24 EXS87RD ACE → BRS Jul 24, 09:30 UTCJul 24, 09:35 UTC5m
2026-07-24 EXS5UG BRS → ACE Jul 24, 06:05 UTCJul 24, 08:45 UTC2h 40m
2026-07-23 EXS99SU BHX → ACE Jul 23, 18:15 UTCJul 23, 20:45 UTC2h 30m
2026-07-23 EXS6CX MAN → ACE Jul 23, 14:50 UTCJul 23, 17:20 UTC2h 30m
2026-07-23 EXS22EF BHX → PSA Jul 23, 11:00 UTCJul 23, 13:30 UTC2h 30m
2026-07-23 EXS56AM LPA → BHX Jul 23, 07:10 UTCJul 23, 09:15 UTC2h 5m
2026-07-22 EXS74ST PMI → BRS Jul 22, 20:10 UTCJul 22, 22:50 UTC2h 40m
2026-07-22 EXS43M ALC → BHX Jul 22, 16:15 UTCJul 22, 18:50 UTC2h 35m
2026-07-22 EXS74DF MAN → FUE Jul 22, 11:50 UTCJul 22, 14:30 UTC2h 40m
2026-07-21 EXS27H MAN → BCN Jul 21, 21:15 UTCJul 22, 01:25 UTC4h 10m
2026-07-21 EXS53J MAN → VCE Jul 21, 16:15 UTCJul 21, 19:55 UTC3h 40m
2026-07-21 EXS804 - Jul 21, 11:30 UTCJul 21, 13:35 UTC2h 5m
2026-07-21 EXS4YZ MAN → BCN Jul 21, 07:30 UTCJul 21, 09:30 UTC2h 0m
2026-07-20 EXS6MT CFU → MAN Jul 20, 17:10 UTCJul 20, 19:05 UTC1h 55m
2026-07-20 EXS13Y PMI → MAN Jul 20, 12:40 UTCJul 20, 14:40 UTC2h 0m
2026-07-20 EXS29V KGS → BRS Jul 20, 09:00 UTCJul 20, 11:05 UTC2h 5m
2026-07-20 EXS89PK FNC → BHX Jul 20, 05:35 UTCJul 20, 07:35 UTC2h 0m
2026-07-19 EXS12DR BHX → KGS Jul 19, 23:10 UTCJul 20, 01:35 UTC2h 25m
2026-07-19 EXS52RD EFL → BHX Jul 19, 19:30 UTCJul 19, 21:50 UTC2h 20m
2026-07-19 EXS042A ATH → MAN Jul 19, 13:45 UTCJul 19, 17:40 UTC3h 55m
2026-07-15 EXS409M - Jul 15, 14:45 UTCJul 15, 18:05 UTC3h 20m
2026-07-15 EXS41M - Jul 15, 10:50 UTCJul 15, 12:45 UTC1h 55m
2026-07-15 EXS85NQ - Jul 15, 07:20 UTCJul 15, 08:45 UTC1h 25m
2026-07-14 EXS66UN XRY → STN Jul 14, 17:10 UTCJul 14, 19:35 UTC2h 25m
2026-07-14 EXS77TB - Jul 14, 13:35 UTCJul 14, 16:15 UTC2h 40m
2026-07-14 EXS42UD - Jul 14, 09:45 UTCJul 14, 12:30 UTC2h 45m
2026-07-14 EXS27KL STN → DBV Jul 14, 06:20 UTCJul 14, 08:30 UTC2h 10m
2026-07-13 EXS76MK - Jul 13, 18:15 UTCJul 13, 21:30 UTC3h 15m
2026-07-13 EXS96BL - Jul 13, 14:20 UTCJul 13, 17:00 UTC2h 40m
2026-07-13 EXS52P - Jul 13, 10:05 UTCJul 13, 12:40 UTC2h 35m
2026-07-13 EXS9AN - Jul 13, 06:30 UTCJul 13, 08:40 UTC2h 10m
2026-07-12 EXS406R - Jul 12, 19:40 UTCJul 12, 22:00 UTC2h 20m
2026-07-12 EXS19G - Jul 12, 15:25 UTCJul 12, 18:15 UTC2h 50m
2026-07-12 EXS42UD DBV → STN Jul 12, 11:25 UTCJul 12, 13:55 UTC2h 30m
2026-07-12 EXS27KL - Jul 12, 07:55 UTCJul 12, 10:10 UTC2h 15m
2026-07-11 EXS14VP HER → STN Jul 11, 21:20 UTCJul 12, 00:55 UTC3h 35m
2026-07-11 EXS7FS - Jul 11, 16:25 UTCJul 11, 19:40 UTC3h 15m
2026-07-11 EXS48CL - Jul 11, 12:35 UTCJul 11, 14:35 UTC2h 0m
2026-07-11 EXS2KC - Jul 11, 07:50 UTCJul 11, 10:00 UTC2h 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-GDFF page for operator, model, and routing details .

Mode-S 4066B9 frequently asked

What is Mode-S code 4066B9?
4066B9 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-GDFF.
Where is Mode-S 4066B9 registered?
Mode-S code 4066B9 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 4066B9 broadcasting right now?
Yes. Mode-S 4066B9 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4066B9, octal 20063271, decimal 4,220,601.
What flights does 4066B9 operate?
Mode-S 4066B9 has broadcast 20 distinct callsigns, including EXS406R, EXS31DR, EXS19G, EXS42UD, EXS27KL.