sensors Mode-S transponder

4D21F7

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-QAK · BOEING 737-800

Hex
4D21F7
Octal
23220767
Decimal
5,054,967
Country
MT
Tail
9H-QAK
Type
B738
Broadcasting now · callsign RYR8ZE · 32,000 ft
Flights observed
270
Distinct callsigns
20
Country
MT
Last broadcast
20m ago

Current position

4D21F7 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D21F7 falls within the block assigned to Malta (MT) by ICAO Annex 10, Volume III. Every aircraft registered in Malta 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
RYR2DG Ryanair 4 2026-05-17
RYR2AA - 4 2026-04-15
RYR29DB Ryanair 4 2026-04-15
RYR8YT Ryanair 3 2026-05-17
RYR7BM Ryanair 3 2026-05-24
RYR76HY Ryanair 3 2026-05-28
RYR76GX - 3 2026-04-15
RYR672C Ryanair 3 2026-05-23
RYR55LG Ryanair 3 2026-05-28
RYR46KZ Ryanair 3 2026-05-28
RYR374M - 3 2026-04-15
RYR10BZ Ryanair 3 2026-05-24
RYR97MQ Ryanair 2 2026-05-18
RYR96SW Ryanair 2 2026-05-23
RYR9678 - 2 2026-04-16
RYR8YU Ryanair 2 2026-05-19
RYR86DZ Ryanair 2 2026-05-29
RYR83BZ Ryanair 2 2026-05-16
RYR7ZN Ryanair 2 2026-04-18
RYR7WV Ryanair 2 2026-04-17

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 RYR8ZE MAD → PMI May 30, 15:35 UTCMay 30, 15:45 UTC10m
2026-05-30 RYR4AF LUX → DUB May 30, 11:10 UTCMay 30, 14:05 UTC2h 55m
2026-05-30 RYR9QK VIE → CTA May 30, 07:10 UTCMay 30, 09:55 UTC2h 45m
2026-05-29 RYR77QE ESU → MAD May 29, 16:50 UTCMay 29, 20:50 UTC4h 0m
2026-05-29 RYR36TZ CRL → MAD May 29, 13:00 UTCMay 29, 14:45 UTC1h 45m
2026-05-29 RYR760R BZR → CRL May 29, 10:45 UTCMay 29, 12:15 UTC1h 30m
2026-05-29 RYR86DZ CRL → BZR May 29, 08:40 UTCMay 29, 09:50 UTC1h 10m
2026-05-29 RYR2CL BLQ → CTA May 29, 06:45 UTCMay 29, 08:00 UTC1h 15m
2026-05-29 RYR52BG CRL → BGY May 29, 04:45 UTCMay 29, 05:50 UTC1h 5m
2026-05-28 RYR46KZ ESU → CRL May 28, 13:30 UTCMay 28, 20:45 UTC7h 15m
2026-05-28 RYR55LG NDR → CRL May 28, 09:45 UTCMay 28, 12:15 UTC2h 30m
2026-05-28 RYR76HY CRL → NDR May 28, 06:00 UTCMay 28, 08:45 UTC2h 45m
2026-05-27 RYR35NN ALC → CRL May 27, 18:25 UTCMay 27, 20:20 UTC1h 55m
2026-05-27 RYR12WW LIS → STN May 27, 15:20 UTCMay 27, 17:15 UTC1h 55m
2026-05-27 RYR68ZA CRL → ESU May 27, 06:15 UTCMay 27, 13:40 UTC7h 25m
2026-05-26 RYR5XL LGW → DUB May 26, 19:25 UTCMay 26, 21:04 UTC1h 40m
2026-05-26 RYR86EW CRL → AHO May 26, 16:45 UTCMay 26, 18:24 UTC1h 40m
2026-05-26 RYR22ZU SDR → CRL May 26, 14:24 UTCMay 26, 15:45 UTC1h 20m
2026-05-26 RYR1ST CFU → VNO May 26, 12:05 UTCMay 26, 13:24 UTC1h 20m
2026-05-26 RYR4MA WRO → PFO May 26, 08:39 UTCMay 26, 10:34 UTC1h 55m
2026-05-26 RYR140E CRL → CAG May 26, 05:40 UTCMay 26, 07:29 UTC1h 50m
2026-05-25 RYR93TK TRN → CRL May 25, 19:05 UTCMay 25, 19:59 UTC55m
2026-05-25 RYR6RK KRK → TRF May 25, 17:05 UTCMay 25, 18:10 UTC1h 5m
2026-05-25 RYR70ZH CFU → CRL May 25, 14:05 UTCMay 25, 16:15 UTC2h 10m
2026-05-25 RYR97UU CRL → CFU May 25, 10:45 UTCMay 25, 13:00 UTC2h 15m
2026-05-25 RYR21LA NAP → CRL May 25, 07:45 UTCMay 25, 09:30 UTC1h 45m
2026-05-25 RYR64CZ VNO → HHN May 25, 04:45 UTCMay 25, 06:40 UTC1h 55m
2026-05-24 RYR63CZ HEL → CRL May 24, 18:35 UTCMay 24, 20:50 UTC2h 15m
2026-05-24 RYR61AT CRL → HEL May 24, 15:10 UTCMay 24, 17:30 UTC2h 20m
2026-05-24 RYR10BZ IBZ → CRL May 24, 12:05 UTCMay 24, 14:00 UTC1h 55m
2026-05-24 RYR7BM BZR → STN May 24, 08:40 UTCMay 24, 10:40 UTC2h 0m
2026-05-24 RYR7WU EIN → DUB May 24, 06:45 UTCMay 24, 07:55 UTC1h 10m
2026-05-24 RYR56DD CRL → TSF May 24, 04:40 UTCMay 24, 05:50 UTC1h 10m
2026-05-23 RYR9647 ATH → CRL May 23, 17:55 UTCMay 23, 20:40 UTC2h 46m
2026-05-23 RYR7KF MAN → FMM May 23, 14:15 UTCMay 23, 16:55 UTC2h 40m
2026-05-23 RYR760R BZR → CRL May 23, 11:40 UTCMay 23, 13:00 UTC1h 20m
2026-05-23 RYR86DZ CRL → BZR May 23, 09:35 UTCMay 23, 10:45 UTC1h 10m
2026-05-23 RYR672C WRO → CRL May 23, 07:05 UTCMay 23, 08:20 UTC1h 15m
2026-05-23 RYR96SW CRL → WRO May 23, 04:50 UTCMay 23, 06:10 UTC1h 20m
2026-05-22 RYR2RG DUB → BER May 22, 17:40 UTCMay 22, 20:00 UTC2h 20m
2026-05-22 RYR515T CRL → OTP May 22, 14:20 UTCMay 22, 16:40 UTC2h 20m
2026-05-22 RYR9HE MAN → MAD May 22, 11:45 UTCMay 22, 13:05 UTC1h 20m
2026-05-22 RYR84MB CRL → CCF May 22, 09:35 UTCMay 22, 10:45 UTC1h 10m
2026-05-22 RYR8MR OPO → BER May 22, 07:05 UTCMay 22, 08:40 UTC1h 35m
2026-05-22 RYR3UX MAN → ALC May 22, 04:40 UTCMay 22, 06:10 UTC1h 30m
2026-05-21 RYR46KZ ESU → CRL May 21, 13:40 UTCMay 21, 20:45 UTC7h 5m
2026-05-21 RYR55LG NDR → CRL May 21, 10:05 UTCMay 21, 12:30 UTC2h 25m
2026-05-21 RYR76HY CRL → NDR May 21, 06:20 UTCMay 21, 09:00 UTC2h 40m
2026-05-20 RYR2AK BVA → NAP May 20, 14:55 UTCMay 20, 17:25 UTC2h 30m
2026-05-20 RYR4EY CRL → OUD May 20, 11:05 UTCMay 20, 13:25 UTC2h 20m

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 9H-QAK page for operator, model, and routing details .

Mode-S 4D21F7 frequently asked

What is Mode-S code 4D21F7?
4D21F7 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-QAK.
Where is Mode-S 4D21F7 registered?
Mode-S code 4D21F7 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D21F7 broadcasting right now?
Yes. Mode-S 4D21F7 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D21F7, octal 23220767, decimal 5,054,967.
What flights does 4D21F7 operate?
Mode-S 4D21F7 has broadcast 20 distinct callsigns, including RYR2DG, RYR2AA, RYR29DB, RYR8YT, RYR7BM.