sensors Mode-S transponder

48C121

ICAO 24-bit transponder address · allocated to Poland

Currently assigned to SP-RKB · BOEING 737-800

Hex
48C121
Octal
22140441
Decimal
4,768,033
Country
PL
Tail
SP-RKB
Type
B738
No current signal · last broadcast Jul 26, 22:15 UTC
Flights observed
703
Distinct callsigns
20
Country
PL
Last broadcast
Jul 26, 22:15 UTC

Last known position

Most recent position reported by Mode-S 48C121.

Country allocation

The ICAO 24-bit address 48C121 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 20 distinct

Callsign Airline Flights Last seen
RYR1501 Ryanair 15 2026-04-25
RYR1502 Ryanair 13 2026-04-25
RYR76CE - 7 2026-07-16
RYR61CH - 7 2026-07-16
RYR8MA Ryanair 6 2026-04-24
RYR5928 - 6 2026-06-20
RYR34RH Ryanair 6 2026-04-25
RYR6PA - 5 2026-07-15
RYR6NP Ryanair 5 2026-05-14
RYR5929 - 5 2026-06-20
RYR5643 Ryanair 5 2026-05-15
RYR4XK Ryanair 5 2026-04-24
RYR4LB - 5 2026-07-18
RYR46CZ - 5 2026-07-15
RYR33XH - 5 2026-07-18
RYR96JG - 4 2026-07-15
RYR9154 Ryanair 4 2026-04-25
RYR6SX - 4 2026-06-19
RYR67HQ - 4 2026-07-15
RYR6048 Ryanair 4 2026-06-18

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RYS3106 - Jul 26, 21:50 UTCJul 26, 22:15 UTC25m
2026-07-26 RYS7227 - Jul 26, 18:25 UTCJul 26, 20:45 UTC2h 20m
2026-07-26 RYS5068 AYT → KRK Jul 26, 15:15 UTCJul 26, 17:35 UTC2h 20m
2026-07-26 RYS5067 KRK → AYT Jul 26, 10:00 UTCJul 26, 12:40 UTC2h 40m
2026-07-26 RYS4198 - Jul 26, 04:05 UTCJul 26, 06:15 UTC2h 10m
2026-07-26 RYS7237 - Jul 26, 00:10 UTCJul 26, 02:55 UTC2h 45m
2026-07-25 RYR4VF CRL → FEZ Jul 25, 20:35 UTCJul 25, 22:35 UTC2h 0m
2026-07-25 RYR2552 POZ → SKG Jul 25, 17:50 UTCJul 25, 19:40 UTC1h 50m
2026-07-25 RYR472L ZAD → POZ Jul 25, 15:55 UTCJul 25, 17:10 UTC1h 15m
2026-07-25 RYR741D POZ → ZAD Jul 25, 13:40 UTCJul 25, 14:50 UTC1h 10m
2026-07-25 RYR64HB ZAD → POZ Jul 25, 11:40 UTCJul 25, 12:55 UTC1h 15m
2026-07-25 RYR7SY BVA → MRS Jul 25, 09:10 UTCJul 25, 10:15 UTC1h 5m
2026-07-25 RYR9YU PMI → EXT Jul 25, 06:35 UTCJul 25, 08:20 UTC1h 45m
2026-07-25 RYR6MU BGY → CPH Jul 25, 04:15 UTCJul 25, 05:50 UTC1h 35m
2026-07-24 RYR65YP DUB → POZ Jul 24, 19:25 UTCJul 24, 21:30 UTC2h 5m
2026-07-24 RYR74HJ CRL → NDR Jul 24, 16:00 UTCJul 24, 18:35 UTC2h 35m
2026-07-24 RYR6NW PMI → LBA Jul 24, 12:40 UTCJul 24, 14:50 UTC2h 10m
2026-07-24 RYR21FE - Jul 24, 09:10 UTCJul 24, 11:45 UTC2h 35m
2026-07-24 RYR6AJ INI → VIE Jul 24, 07:15 UTCJul 24, 08:15 UTC1h 0m
2026-07-24 RYR2DH FAO → TLS Jul 24, 05:25 UTCJul 24, 06:15 UTC50m
2026-07-23 RYR40CR ATH → WMI Jul 23, 19:45 UTCJul 23, 21:55 UTC2h 10m
2026-07-23 RYR20AX WMI → ATH Jul 23, 16:35 UTCJul 23, 18:45 UTC2h 10m
2026-07-23 RYR824W BVA → WMI Jul 23, 13:35 UTCJul 23, 15:40 UTC2h 5m
2026-07-23 RYR54BW WMI → BVA Jul 23, 10:55 UTCJul 23, 12:45 UTC1h 50m
2026-07-23 RYR7FV AMM → VIE Jul 23, 07:40 UTCJul 23, 09:35 UTC1h 55m
2026-07-23 RYR34BB WMI → CIA Jul 23, 04:40 UTCJul 23, 06:30 UTC1h 50m
2026-07-22 RYR4AY - Jul 22, 20:15 UTCJul 22, 21:40 UTC1h 25m
2026-07-22 RYR35ZQ WMI → BGY Jul 22, 17:25 UTCJul 22, 19:05 UTC1h 40m
2026-07-22 RYR1HV TUF → RAK Jul 22, 14:55 UTCJul 22, 16:45 UTC1h 50m
2026-07-22 RYR8UB AGP → BUD Jul 22, 11:35 UTCJul 22, 13:10 UTC1h 35m
2026-07-22 RYR70CR WMI → MLA Jul 22, 04:10 UTCJul 22, 10:25 UTC6h 15m
2026-07-21 RYR8704 PRG → EDI Jul 21, 21:05 UTCJul 21, 22:20 UTC1h 15m
2026-07-21 RYR7XL LBA → WMI Jul 21, 18:55 UTCJul 21, 20:15 UTC1h 20m
2026-07-21 RYR47TK PMO → WMI Jul 21, 16:00 UTCJul 21, 18:15 UTC2h 15m
2026-07-21 RYR4057 AGP → HAM Jul 21, 12:35 UTCJul 21, 14:55 UTC2h 20m
2026-07-21 RYR12HZ MLA → WMI Jul 21, 07:15 UTCJul 21, 09:55 UTC2h 40m
2026-07-21 RYR70CR WMI → MLA Jul 21, 03:55 UTCJul 21, 06:30 UTC2h 35m
2026-07-20 RYR44EB - Jul 20, 19:15 UTCJul 20, 21:45 UTC2h 30m
2026-07-20 RYR69LP - Jul 20, 15:15 UTCJul 20, 18:10 UTC2h 55m
2026-07-20 RYR2QK MLA → WMI Jul 20, 10:15 UTCJul 20, 12:50 UTC2h 35m
2026-07-20 RYR4QV SVQ → EIN Jul 20, 06:40 UTCJul 20, 09:25 UTC2h 45m
2026-07-19 RYR47TK - Jul 19, 19:10 UTCJul 19, 21:15 UTC2h 5m
2026-07-19 RYR4057 AGP → HAM Jul 19, 15:45 UTCJul 19, 18:15 UTC2h 30m
2026-07-19 RYR8704 PRG → EDI Jul 19, 13:15 UTCJul 19, 14:30 UTC1h 15m
2026-07-19 RYR7XL LBA → WMI Jul 19, 11:00 UTCJul 19, 12:10 UTC1h 10m
2026-07-19 RYR88MT - Jul 19, 07:15 UTCJul 19, 09:50 UTC2h 35m
2026-07-19 RYR7492 WMI → RHO Jul 19, 03:45 UTCJul 19, 06:20 UTC2h 35m
2026-07-18 RYR49BG LIS → BGY Jul 18, 21:15 UTCJul 19, 00:00 UTC2h 45m
2026-07-18 RYR2DD - Jul 18, 16:40 UTCJul 18, 19:55 UTC3h 15m
2026-07-18 RYR95LQ - Jul 18, 12:40 UTCJul 18, 14:10 UTC1h 30m

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-RKB page for operator, model, and routing details .

Mode-S 48C121 frequently asked

What is Mode-S code 48C121?
48C121 is an ICAO 24-bit transponder address. Allocated to Poland. Assigned to SP-RKB.
Where is Mode-S 48C121 registered?
Mode-S code 48C121 is allocated to Poland (PL). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 48C121 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:15 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 48C121, octal 22140441, decimal 4,768,033.
What flights does 48C121 operate?
Mode-S 48C121 has broadcast 20 distinct callsigns, including RYR1501, RYR1502, RYR76CE, RYR61CH, RYR8MA.