sensors Mode-S transponder

424501

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to VQ-BHF · BOEING 737-800

Hex
424501
Octal
20442401
Decimal
4,343,041
Country
GB
Tail
VQ-BHF
Type
B738
No current signal · last broadcast 8h ago
Flights observed
50
Distinct callsigns
18
Country
GB
Last broadcast
8h ago

Last known position

Most recent position reported by Mode-S 424501.

Country allocation

The ICAO 24-bit address 424501 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

Callsign Airline Flights Last seen
SMR275 Somon Air 14 2026-05-27
SMR375 Somon Air 7 2026-04-24
SMR337 Somon Air 4 2026-04-19
SMR331 Somon Air 4 2026-05-09
SMR231 Somon Air 4 2026-05-29
SMR203 Somon Air 3 2026-05-10
SMR213 Somon Air 2 2026-05-25
SMR105 Somon Air 2 2026-05-02
SMR376 Somon Air 1 2026-05-12
SMR332 Somon Air 1 2026-04-30
SMR232 Somon Air 1 2026-05-27
SMR222 - 1 2026-04-15
SMR221 Somon Air 1 2026-05-28
SMR214 - 1 2026-04-13
SMR209 - 1 2026-04-14
SMR204 Somon Air 1 2026-04-20
SMR110 Somon Air 1 2026-05-11
SMR109 Somon Air 1 2026-05-10

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 SMR231 DYU → LED May 29, 09:10 UTCMay 29, 21:40 UTC12h 30m
2026-05-28 SMR221 DYU → OVB May 28, 19:40 UTCMay 29, 09:35 UTC13h 55m
2026-05-27 SMR275 LBD → ZIA May 27, 21:55 UTCMay 28, 20:00 UTC22h 5m
2026-05-27 SMR275 LBD → ZIA May 27, 00:55 UTCMay 27, 18:10 UTC17h 15m
2026-05-27 SMR232 LED → DYU May 27, 00:04 UTCMay 27, 00:19 UTC15m
2026-05-26 SMR231 DYU → LED May 26, 21:55 UTCMay 26, 22:05 UTC10m
2026-05-25 SMR213 DYU → KJA May 25, 06:20 UTCMay 26, 01:05 UTC18h 44m
2026-05-16 SMR275 LBD → ZIA May 16, 17:35 UTCMay 16, 18:00 UTC25m
2026-05-15 SMR231 DYU → LED May 15, 20:55 UTCMay 16, 18:00 UTC21h 6m
2026-05-14 SMR275 LBD → ZIA May 14, 19:40 UTCMay 14, 20:05 UTC25m
2026-05-13 SMR275 LBD → ZIA May 13, 17:30 UTCMay 13, 18:10 UTC40m
2026-05-12 SMR376 ZIA → LBD May 12, 22:31 UTCMay 12, 22:55 UTC25m
2026-05-11 SMR110 DEL → DYU May 11, 11:05 UTCMay 11, 22:15 UTC11h 11m
2026-05-10 SMR109 DYU → DEL May 10, 20:05 UTCMay 11, 09:10 UTC13h 5m
2026-05-10 SMR203 DYU → LED May 10, 00:24 UTCMay 10, 20:30 UTC20h 5m
2026-05-09 SMR331 DYU → ZIA May 9, 20:34 UTCMay 10, 20:14 UTC23h 40m
2026-05-07 SMR203 DYU → LED May 7, 21:25 UTCMay 8, 10:04 UTC12h 40m
2026-05-06 SMR331 DYU → ZIA May 6, 09:40 UTCMay 6, 20:00 UTC10h 19m
2026-05-04 SMR275 LBD → ZIA May 4, 20:00 UTCMay 4, 20:45 UTC45m
2026-05-03 SMR275 LBD → ZIA May 3, 17:45 UTCMay 3, 18:25 UTC40m
2026-05-02 SMR275 LBD → ZIA May 2, 22:40 UTCMay 3, 18:25 UTC19h 44m
2026-05-02 SMR275 LBD → ZIA May 2, 19:05 UTCMay 3, 18:14 UTC23h 9m
2026-05-02 SMR105 DYU → DXB May 2, 17:10 UTCMay 3, 00:15 UTC7h 5m
2026-04-30 SMR332 ZIA → DYU Apr 30, 23:55 UTCMay 1, 00:20 UTC25m
2026-04-27 SMR275 LBD → ZIA Apr 27, 19:40 UTCApr 27, 20:20 UTC40m
2026-04-26 SMR275 LBD → ZIA Apr 26, 19:10 UTCApr 26, 19:55 UTC45m
2026-04-24 SMR375 LBD → ZIA Apr 24, 21:15 UTCApr 25, 10:20 UTC13h 5m
2026-04-24 SMR375 LBD → ZIA Apr 24, 13:25 UTCApr 25, 10:20 UTC20h 55m
2026-04-24 SMR375 LBD → ZIA Apr 24, 04:00 UTCApr 25, 00:45 UTC20h 45m
2026-04-24 SMR375 LBD → ZIA Apr 24, 00:20 UTCApr 24, 22:00 UTC21h 40m
2026-04-24 SMR375 LBD → ZIA Apr 24, 00:05 UTCApr 24, 22:00 UTC21h 55m
2026-04-22 SMR275 LBD → ZIA Apr 22, 17:35 UTCApr 22, 18:15 UTC40m
2026-04-21 SMR275 LBD → ZIA Apr 21, 21:50 UTCApr 22, 18:15 UTC20h 25m
2026-04-21 SMR275 LBD → ZIA Apr 21, 18:20 UTCApr 22, 18:15 UTC23h 55m
2026-04-21 SMR375 LBD → ZIA Apr 21, 17:40 UTCApr 21, 21:55 UTC4h 15m
2026-04-20 SMR375 LBD → ZIA Apr 20, 21:25 UTCApr 21, 18:20 UTC20h 55m
2026-04-20 SMR331 DYU → ZIA Apr 20, 03:00 UTCApr 20, 21:40 UTC18h 40m
2026-04-20 SMR204 LED → DYU Apr 20, 02:05 UTCApr 20, 21:40 UTC19h 35m
2026-04-19 SMR203 DYU → LED Apr 19, 21:35 UTCApr 20, 03:10 UTC5h 35m
2026-04-19 SMR337 DYU → ZIA Apr 19, 06:20 UTCApr 20, 03:10 UTC20h 50m
2026-04-19 SMR337 DYU → ZIA Apr 19, 06:05 UTCApr 20, 03:10 UTC21h 5m
2026-04-18 SMR337 DYU → ZIA Apr 18, 21:45 UTCApr 19, 06:45 UTC9h 0m
2026-04-18 SMR105 DYU → DXB Apr 18, 18:40 UTCApr 18, 19:10 UTC30m
2026-04-16 SMR337 DYU → ZIA Apr 16, 06:05 UTCApr 16, 06:45 UTC40m
2026-04-15 SMR222 - Apr 15, 09:55 UTCApr 15, 10:20 UTC25m
2026-04-14 SMR209 - Apr 14, 09:10 UTCApr 14, 09:30 UTC20m
2026-04-13 SMR331 - Apr 13, 21:45 UTCApr 13, 22:20 UTC35m
2026-04-13 SMR214 - Apr 13, 10:05 UTCApr 13, 11:35 UTC1h 30m
2026-04-13 SMR213 DYU → KJA Apr 13, 06:00 UTCApr 13, 07:20 UTC1h 20m
2026-04-12 SMR231 - Apr 12, 19:10 UTCApr 12, 20:10 UTC1h 0m

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

Mode-S 424501 frequently asked

What is Mode-S code 424501?
424501 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to VQ-BHF.
Where is Mode-S 424501 registered?
Mode-S code 424501 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 424501 broadcasting right now?
No active broadcast right now. Last signal was 8h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 424501, octal 20442401, decimal 4,343,041.
What flights does 424501 operate?
Mode-S 424501 has broadcast 18 distinct callsigns, including SMR275, SMR375, SMR337, SMR331, SMR231.