sensors Mode-S transponder

48C139

ICAO 24-bit transponder address · allocated to Poland

Currently assigned to SP-RKQ · BOEING 737-800

Hex
48C139
Octal
22140471
Decimal
4,768,057
Country
PL
Tail
SP-RKQ
Type
B738
No current signal · last broadcast 13h ago
Flights observed
13
Distinct callsigns
11
Country
PL
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S 48C139.

Country allocation

The ICAO 24-bit address 48C139 falls within the block assigned to Poland (PL) by ICAO Annex 10, Volume III. Every aircraft registered in Poland 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 11 distinct

Callsign Airline Flights Last seen
RYR8658 - 2 2026-04-14
RYR28GL - 2 2026-04-13
RYR93SC - 1 2026-04-13
RYR81YQ - 1 2026-04-12
RYR70SV - 1 2026-04-13
RYR5WW - 1 2026-04-13
RYR57YU - 1 2026-04-13
RYR4JT - 1 2026-04-13
RYR44SA - 1 2026-04-14
RYR1LC - 1 2026-04-13
RYR16YG - 1 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-14 RYR8658 - Apr 14, 09:10 UTCApr 14, 10:15 UTC1h 5m
2026-04-14 RYR8658 - Apr 14, 07:50 UTCApr 14, 09:05 UTC1h 15m
2026-04-14 RYR44SA - Apr 14, 05:15 UTCApr 14, 06:50 UTC1h 35m
2026-04-13 RYR93SC - Apr 13, 20:40 UTCApr 13, 21:35 UTC55m
2026-04-13 RYR70SV - Apr 13, 18:50 UTCApr 13, 19:45 UTC55m
2026-04-13 RYR16YG - Apr 13, 16:55 UTCApr 13, 18:00 UTC1h 5m
2026-04-13 RYR4JT - Apr 13, 14:55 UTCApr 13, 15:50 UTC55m
2026-04-13 RYR5WW - Apr 13, 12:20 UTCApr 13, 13:30 UTC1h 10m
2026-04-13 RYR1LC - Apr 13, 10:00 UTCApr 13, 11:05 UTC1h 5m
2026-04-13 RYR28GL - Apr 13, 08:20 UTCApr 13, 08:50 UTC30m
2026-04-13 RYR28GL - Apr 13, 08:05 UTCApr 13, 08:15 UTC10m
2026-04-13 RYR57YU - Apr 13, 06:35 UTCApr 13, 07:20 UTC45m
2026-04-12 RYR81YQ - Apr 12, 18:05 UTCApr 12, 20:00 UTC1h 55m

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 SP-RKQ page for operator, model, and routing details .

Mode-S 48C139 frequently asked

What is Mode-S code 48C139?
48C139 is an ICAO 24-bit transponder address. Allocated to Poland. Assigned to SP-RKQ.
Where is Mode-S 48C139 registered?
Mode-S code 48C139 is allocated to Poland (PL). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 48C139 broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 48C139, octal 22140471, decimal 4,768,057.
What flights does 48C139 operate?
Mode-S 48C139 has broadcast 11 distinct callsigns, including RYR8658, RYR28GL, RYR93SC, RYR81YQ, RYR70SV.