sensors Mode-S transponder

40837A

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-FABV · EMBRAER EMB-500 Phenom 100

Hex
40837A
Octal
20101572
Decimal
4,227,962
Country
GB
Tail
G-FABV
Type
E50P
No current signal · last broadcast 2h ago
Flights observed
7
Distinct callsigns
2
Country
GB
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 40837A.

Country allocation

The ICAO 24-bit address 40837A 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
GFABV - 6 2026-07-01
GFABVXX - 1 2026-06-10

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-07-01 GFABV - Jul 1, 18:50 UTCJul 1, 19:20 UTC30m
2026-07-01 GFABV - Jul 1, 16:10 UTCJul 1, 16:45 UTC35m
2026-07-01 GFABV - Jul 1, 14:40 UTCJul 1, 15:20 UTC40m
2026-07-01 GFABV CWL → BHX Jul 1, 12:15 UTCJul 1, 12:55 UTC40m
2026-07-01 GFABV - Jul 1, 10:45 UTCJul 1, 11:30 UTC45m
2026-06-26 GFABV - Jun 26, 08:24 UTCJun 26, 08:54 UTC30m
2026-06-10 GFABVXX - Jun 10, 12:40 UTCJun 10, 13:45 UTC1h 5m

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

Mode-S 40837A frequently asked

What is Mode-S code 40837A?
40837A is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-FABV.
Where is Mode-S 40837A registered?
Mode-S code 40837A 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 40837A broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 40837A, octal 20101572, decimal 4,227,962.
What flights does 40837A operate?
Mode-S 40837A has broadcast 2 distinct callsigns, including GFABV, GFABVXX.