sensors Mode-S transponder

4D029D

ICAO 24-bit transponder address · allocated to Luxembourg

Currently assigned to LX-SEH

Hex
4D029D
Octal
23201235
Decimal
5,046,941
Country
LU
Tail
LX-SEH
Type
C56X
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
LU
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4D029D.

Country allocation

The ICAO 24-bit address 4D029D falls within the block assigned to Luxembourg (LU) by ICAO Annex 10, Volume III. Every aircraft registered in Luxembourg 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 1 distinct

Callsign Airline Flights Last seen
JFA97Z - 5 2026-05-11

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-11 JFA97Z - May 11, 15:25 UTCMay 11, 17:20 UTC1h 56m
2026-05-10 JFA97Z - May 10, 13:30 UTCMay 10, 14:54 UTC1h 25m
2026-05-10 JFA97Z - May 10, 10:35 UTCMay 10, 11:45 UTC1h 10m
2026-04-28 JFA97Z - Apr 28, 15:30 UTCApr 28, 16:20 UTC50m
2026-04-28 JFA97Z BXO → LUX Apr 28, 13:05 UTCApr 28, 13:55 UTC50m

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 LX-SEH page for operator, model, and routing details .

Mode-S 4D029D frequently asked

What is Mode-S code 4D029D?
4D029D is an ICAO 24-bit transponder address. Allocated to Luxembourg. Assigned to LX-SEH.
Where is Mode-S 4D029D registered?
Mode-S code 4D029D is allocated to Luxembourg (LU). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D029D 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 4D029D, octal 23201235, decimal 5,046,941.
What flights does 4D029D operate?
Mode-S 4D029D has broadcast 1 distinct callsign, including JFA97Z.