sensors Mode-S transponder

407B4B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-COMS · DIAMOND DA-42 Guardian

Hex
407B4B
Octal
20075513
Decimal
4,225,867
Country
GB
Tail
G-COMS
Type
DA42
Photo of G-COMS
No current signal · last broadcast 18h ago
Flights observed
4
Distinct callsigns
2
Country
GB
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S 407B4B.

Country allocation

The ICAO 24-bit address 407B4B 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 2 distinct

Callsign Airline Flights Last seen
SFY4PC - 2 2026-04-14
EXM18 - 2 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-14 SFY4PC - Apr 14, 10:40 UTCApr 14, 11:05 UTC25m
2026-04-13 EXM18 - Apr 13, 14:30 UTCApr 13, 15:50 UTC1h 20m
2026-04-13 SFY4PC - Apr 13, 12:40 UTCApr 13, 13:45 UTC1h 5m
2026-04-13 EXM18 GLO → GLO Apr 13, 10:05 UTCApr 13, 11:40 UTC1h 35m

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

Mode-S 407B4B frequently asked

What is Mode-S code 407B4B?
407B4B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-COMS.
Where is Mode-S 407B4B registered?
Mode-S code 407B4B 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 407B4B broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 407B4B, octal 20075513, decimal 4,225,867.
What flights does 407B4B operate?
Mode-S 407B4B has broadcast 2 distinct callsigns, including SFY4PC, EXM18.