sensors Mode-S transponder

4D0290

ICAO 24-bit transponder address · allocated to Luxembourg

Currently assigned to LX-RSQ · LEARJET 45

Hex
4D0290
Octal
23201220
Decimal
5,046,928
Country
LU
Tail
LX-RSQ
Type
LJ45
No current signal · last broadcast 34m ago
Flights observed
4
Distinct callsigns
2
Country
LU
Last broadcast
34m ago

Last known position

Most recent position reported by Mode-S 4D0290.

Country allocation

The ICAO 24-bit address 4D0290 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 2 distinct

Callsign Airline Flights Last seen
LRQ216F - 3 2026-05-23
LRQ209J - 1 2026-05-21

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-05-23 LRQ216F - May 23, 19:20 UTCMay 23, 20:00 UTC40m
2026-05-23 LRQ216F - May 23, 17:50 UTCMay 23, 18:55 UTC1h 5m
2026-05-23 LRQ216F - May 23, 11:35 UTCMay 23, 14:10 UTC2h 35m
2026-05-21 LRQ209J NUE → LUX May 21, 15:45 UTCMay 21, 16:25 UTC40m

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

Mode-S 4D0290 frequently asked

What is Mode-S code 4D0290?
4D0290 is an ICAO 24-bit transponder address. Allocated to Luxembourg. Assigned to LX-RSQ.
Where is Mode-S 4D0290 registered?
Mode-S code 4D0290 is allocated to Luxembourg (LU). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D0290 broadcasting right now?
No active broadcast right now. Last signal was 34m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D0290, octal 23201220, decimal 5,046,928.
What flights does 4D0290 operate?
Mode-S 4D0290 has broadcast 2 distinct callsigns, including LRQ216F, LRQ209J.