sensors Mode-S transponder

503D1B

ICAO 24-bit transponder address · allocated to Lithuania

Currently assigned to LY-BGD

Hex
503D1B
Octal
24036433
Decimal
5,258,523
Country
LT
Tail
LY-BGD
Type
H25B
No current signal · last broadcast 4h ago
Flights observed
5
Distinct callsigns
3
Country
LT
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S 503D1B.

Country allocation

The ICAO 24-bit address 503D1B 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 3 distinct

Callsign Airline Flights Last seen
SZN331 - 2 2026-06-21
SZN332 - 1 2026-06-22
SZN306 - 1 2026-06-26

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-26 SZN306 - Jun 26, 19:14 UTCJun 26, 19:45 UTC30m
2026-06-22 SZN332 - Jun 22, 12:34 UTCJun 22, 12:49 UTC15m
2026-06-21 SZN331 - Jun 21, 05:00 UTCJun 21, 05:10 UTC10m
2026-06-21 - - Jun 21, 01:30 UTCJun 21, 01:39 UTC10m
2026-06-05 SZN331 DSS → CMN Jun 5, 05:15 UTCJun 5, 05:25 UTC10m

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 LY-BGD page for operator, model, and routing details .

Mode-S 503D1B frequently asked

What is Mode-S code 503D1B?
503D1B is an ICAO 24-bit transponder address. Allocated to Lithuania. Assigned to LY-BGD.
Where is Mode-S 503D1B registered?
Mode-S code 503D1B is allocated to Lithuania (LT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 503D1B broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 503D1B, octal 24036433, decimal 5,258,523.
What flights does 503D1B operate?
Mode-S 503D1B has broadcast 3 distinct callsigns, including SZN331, SZN332, SZN306.