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 2h ago
Flights observed
320
Distinct callsigns
20
Country
PL
Last broadcast
2h ago

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
RYR8MA Ryanair 6 2026-04-24
RYR34RH Ryanair 6 2026-04-25
RYR6NP Ryanair 5 2026-05-14
RYR5643 Ryanair 5 2026-05-15
RYR4XK Ryanair 5 2026-04-24
RYR9154 Ryanair 4 2026-04-25
RYR76CE Ryanair 4 2026-05-12
RYR61CH Ryanair 4 2026-05-12
RYR4RQ - 4 2026-04-23
RYR478T Ryanair 4 2026-04-24
RYR200F Ryanair 4 2026-04-24
RYR1856 Ryanair 4 2026-04-20
RYR15BH Ryanair 4 2026-04-23
RYR98FC - 3 2026-05-24
RYR973Z Ryanair 3 2026-04-23
RYR96JG Ryanair 3 2026-05-14
RYR84KW - 3 2026-04-26
RYR7TV Ryanair 3 2026-05-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 RYR4899 BRI → DBV May 29, 22:25 UTCMay 29, 22:55 UTC30m
2026-05-29 RYR6SX DBV → BRI May 29, 21:20 UTCMay 29, 21:45 UTC25m
2026-05-29 RYR75YT MAN → DBV May 29, 18:00 UTCMay 29, 20:30 UTC2h 30m
2026-05-29 RYR14DC PFO → FCO May 29, 14:15 UTCMay 29, 17:10 UTC2h 55m
2026-05-29 RYR9LX STN → FKB May 29, 11:55 UTCMay 29, 12:55 UTC1h 0m
2026-05-29 RYR3HM GDN → STN May 29, 10:05 UTCMay 29, 11:05 UTC1h 0m
2026-05-29 RYR5938 BVA → DBV May 29, 07:25 UTCMay 29, 09:20 UTC1h 55m
2026-05-29 RYR5939 DBV → BVA May 29, 04:20 UTCMay 29, 06:25 UTC2h 5m
2026-05-28 RYR6048 HEL → DBV May 28, 18:50 UTCMay 28, 21:50 UTC3h 0m
2026-05-28 RYR42FH DBV → HEL May 28, 15:00 UTCMay 28, 18:35 UTC3h 35m
2026-05-28 RYR5978 BER → DBV May 28, 11:50 UTCMay 28, 13:25 UTC1h 35m
2026-05-28 RYR5979 DBV → BER May 28, 09:05 UTCMay 28, 10:55 UTC1h 50m
2026-05-28 RYR20YG MRS → DBV May 28, 06:50 UTCMay 28, 08:20 UTC1h 30m
2026-05-28 RYR79YV KRK → PSA May 28, 04:10 UTCMay 28, 05:50 UTC1h 40m
2026-05-27 RYR3DR TRN → MAD May 27, 20:00 UTCMay 27, 22:10 UTC2h 10m
2026-05-27 RYR92YX DBV → STN May 27, 16:30 UTCMay 27, 19:05 UTC2h 35m
2026-05-27 RYR5934 FKB → OPO May 27, 14:35 UTCMay 27, 15:40 UTC1h 5m
2026-05-27 RYR5935 DBV → BGY May 27, 12:30 UTCMay 27, 13:35 UTC1h 5m
2026-05-27 RYR5929 TRF → DBV May 27, 07:20 UTCMay 27, 09:45 UTC2h 25m
2026-05-27 RYR5928 CPH → BGY May 27, 03:45 UTCMay 27, 06:29 UTC2h 45m
2026-05-26 RYR9LX STN → FKB May 26, 20:29 UTCMay 26, 21:25 UTC55m
2026-05-26 RYR3HM GDN → STN May 26, 18:30 UTCMay 26, 19:30 UTC1h 0m
2026-05-26 RYR5933 NRN → DBV May 26, 15:49 UTCMay 26, 17:39 UTC1h 50m
2026-05-26 RYR5932 DBV → NRN May 26, 13:04 UTCMay 26, 15:00 UTC1h 55m
2026-05-26 RYR25YV - May 26, 10:39 UTCMay 26, 11:34 UTC55m
2026-05-26 RYR7NV PSA → PIK May 26, 08:24 UTCMay 26, 09:15 UTC50m
2026-05-26 RYR221H WRO → DBV May 26, 06:20 UTCMay 26, 07:40 UTC1h 20m
2026-05-26 RYR13YT DBV → WRO May 26, 03:50 UTCMay 26, 05:15 UTC1h 25m
2026-05-25 RYR4899 BRI → DBV May 25, 22:05 UTCMay 25, 22:30 UTC25m
2026-05-25 RYR6SX DBV → BRI May 25, 20:50 UTCMay 25, 21:15 UTC25m
2026-05-25 RYR6048 HEL → DBV May 25, 17:40 UTCMay 25, 20:15 UTC2h 34m
2026-05-25 RYR42FH DBV → HEL May 25, 13:50 UTCMay 25, 16:45 UTC2h 55m
2026-05-25 RYR221H WRO → DBV May 25, 11:20 UTCMay 25, 12:45 UTC1h 25m
2026-05-25 RYS39 - May 25, 02:55 UTCMay 25, 04:40 UTC1h 45m
2026-05-24 RYS3106 - May 24, 23:00 UTCMay 24, 23:15 UTC15m
2026-05-24 RYS3106 - May 24, 21:00 UTCMay 24, 21:50 UTC50m
2026-05-24 RYS7227 - May 24, 17:15 UTCMay 24, 19:35 UTC2h 20m
2026-05-24 RYR7TV EMA → GRO May 24, 13:50 UTCMay 24, 15:35 UTC1h 45m
2026-05-24 RYR98FC POZ → DBV May 24, 11:30 UTCMay 24, 13:00 UTC1h 30m
2026-05-24 RYR6FL STN → ARN May 24, 07:20 UTCMay 24, 08:55 UTC1h 35m
2026-05-24 RYR3458 VIT → BGY May 24, 04:55 UTCMay 24, 06:15 UTC1h 20m
2026-05-23 RYR4VF CRL → FEZ May 23, 20:50 UTCMay 23, 22:10 UTC1h 20m
2026-05-23 RYR2552 POZ → SKG May 23, 17:50 UTCMay 23, 19:45 UTC1h 55m
2026-05-23 RYR472L ZAD → POZ May 23, 15:35 UTCMay 23, 16:55 UTC1h 20m
2026-05-23 RYR741D POZ → ZAD May 23, 13:35 UTCMay 23, 14:50 UTC1h 15m
2026-05-23 RYR64HB ZAD → POZ May 23, 11:20 UTCMay 23, 12:45 UTC1h 25m
2026-05-23 RYR7SY BVA → MRS May 23, 09:25 UTCMay 23, 10:40 UTC1h 15m
2026-05-23 RYR9YU PMI → EXT May 23, 06:35 UTCMay 23, 08:30 UTC1h 55m
2026-05-23 RYR6MU BGY → CPH May 23, 04:15 UTCMay 23, 05:50 UTC1h 35m
2026-05-22 RYR9996 PMI → DUB May 22, 23:30 UTCMay 23, 01:10 UTC1h 40m

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 2h ago.
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, RYR8MA, RYR34RH, RYR6NP.