sensors Mode-S transponder

4D24EF

ICAO 24-bit transponder address

Currently assigned to 9H-BCT · GULFSTREAM G650

Hex
4D24EF
Octal
23222357
Decimal
5,055,727
Tail
9H-BCT
Type
GLF6
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
-
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4D24EF.

Callsign history 1 distinct

Callsign Airline Flights Last seen
TYJ535 - 5 2026-06-21

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-21 TYJ535 - Jun 21, 12:24 UTCJun 21, 13:00 UTC35m
2026-06-13 TYJ535 - Jun 13, 07:40 UTCJun 13, 08:00 UTC20m
2026-06-12 TYJ535 ZRH → NCE Jun 12, 16:40 UTCJun 12, 17:30 UTC50m
2026-06-10 TYJ535 - Jun 10, 07:40 UTCJun 10, 08:30 UTC50m
2026-06-08 TYJ535 - Jun 8, 21:45 UTCJun 9, 03:35 UTC5h 50m

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 9H-BCT page for operator, model, and routing details .

Mode-S 4D24EF frequently asked

What is Mode-S code 4D24EF?
4D24EF is an ICAO 24-bit transponder address. Assigned to 9H-BCT.
Is 4D24EF 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 4D24EF, octal 23222357, decimal 5,055,727.
What flights does 4D24EF operate?
Mode-S 4D24EF has broadcast 1 distinct callsign, including TYJ535.