sensors Mode-S transponder

4D03C4

ICAO 24-bit transponder address · allocated to Luxembourg

Currently assigned to LX-N90446 · Boeing E-3A Sentry

Hex
4D03C4
Octal
23201704
Decimal
5,047,236
Country
LU
Tail
LX-N90446
Type
E3TF
No current signal · last broadcast Jul 7, 18:05 UTC
Flights observed
1
Distinct callsigns
1
Country
LU
Last broadcast
Jul 7, 18:05 UTC

Last known position

Most recent position reported by Mode-S 4D03C4.

Country allocation

The ICAO 24-bit address 4D03C4 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
NATO69 - 1 2026-07-07

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-07-07 NATO69 VCE → VCE Jul 7, 12:55 UTCJul 7, 18:00 UTC5h 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 LX-N90446 page for operator, model, and routing details .

Mode-S 4D03C4 frequently asked

What is Mode-S code 4D03C4?
4D03C4 is an ICAO 24-bit transponder address. Allocated to Luxembourg. Assigned to LX-N90446.
Where is Mode-S 4D03C4 registered?
Mode-S code 4D03C4 is allocated to Luxembourg (LU). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D03C4 broadcasting right now?
No active broadcast right now. Last signal was Jul 7, 18:05 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D03C4, octal 23201704, decimal 5,047,236.
What flights does 4D03C4 operate?
Mode-S 4D03C4 has broadcast 1 distinct callsign, including NATO69.