sensors Mode-S transponder

503C4C

ICAO 24-bit transponder address · allocated to Lithuania

Currently assigned to LY-JUA · ATR-72-500

Hex
503C4C
Octal
24036114
Decimal
5,258,316
Country
LT
Tail
LY-JUA
Type
AT75
No current signal · last broadcast 7h ago
Flights observed
6
Distinct callsigns
4
Country
LT
Last broadcast
7h ago

Last known position

Most recent position reported by Mode-S 503C4C.

Country allocation

The ICAO 24-bit address 503C4C 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 4 distinct

Callsign Airline Flights Last seen
SQB942 - 2 2026-07-17
JUP9901 - 2 2026-05-07
SQB944 - 1 2026-07-21
SQB940 - 1 2026-07-18

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-07-21 SQB944 - Jul 21, 05:15 UTCJul 21, 05:30 UTC15m
2026-07-18 SQB940 - Jul 18, 05:45 UTCJul 18, 06:00 UTC15m
2026-07-17 SQB942 - Jul 17, 05:35 UTCJul 17, 05:55 UTC20m
2026-07-16 SQB942 - Jul 16, 05:35 UTCJul 16, 05:45 UTC10m
2026-05-07 JUP9901 - May 7, 10:20 UTCMay 7, 13:30 UTC3h 10m
2026-04-16 JUP9901 - Apr 16, 14:30 UTCApr 16, 14:40 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-JUA page for operator, model, and routing details .

Mode-S 503C4C frequently asked

What is Mode-S code 503C4C?
503C4C is an ICAO 24-bit transponder address. Allocated to Lithuania. Assigned to LY-JUA.
Where is Mode-S 503C4C registered?
Mode-S code 503C4C is allocated to Lithuania (LT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 503C4C broadcasting right now?
No active broadcast right now. Last signal was 7h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 503C4C, octal 24036114, decimal 5,258,316.
What flights does 503C4C operate?
Mode-S 503C4C has broadcast 4 distinct callsigns, including SQB942, JUP9901, SQB944, SQB940.