sensors Mode-S transponder

503D61

ICAO 24-bit transponder address · allocated to Lithuania

Hex
503D61
Octal
24036541
Decimal
5,258,593
Country
LT
No current signal · last broadcast Jun 20, 18:49 UTC
Flights observed
1
Distinct callsigns
1
Country
LT
Last broadcast
Jun 20, 18:49 UTC

Last known position

Most recent position reported by Mode-S 503D61.

Country allocation

The ICAO 24-bit address 503D61 falls within the block assigned to Lithuania (LT) by ICAO Annex 10, Volume III. Every aircraft registered in Lithuania 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
HOT2322 - 1 2026-06-20

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-06-20 HOT2322 - Jun 20, 18:34 UTCJun 20, 18:49 UTC15m

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.

Mode-S 503D61 frequently asked

What is Mode-S code 503D61?
503D61 is an ICAO 24-bit transponder address. Allocated to Lithuania.
Where is Mode-S 503D61 registered?
Mode-S code 503D61 is allocated to Lithuania (LT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 503D61 broadcasting right now?
No active broadcast right now. Last signal was Jun 20, 18:49 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 503D61, octal 24036541, decimal 5,258,593.
What flights does 503D61 operate?
Mode-S 503D61 has broadcast 1 distinct callsign, including HOT2322.