Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

4D21EF

ICAO 24-bit transponder address · allocated to Malta

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

Hex
4D21EF
Octal
23220757
Decimal
5,054,959
Country
MT
Tail
9H-QAG
Type
B738
Broadcasting now · callsign RYR8ZF · 13,050 ft
Flights observed
316
Distinct callsigns
20
Country
MT
Last broadcast
2h ago

Current position

4D21EF is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D21EF 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
RYR29BC Ryanair 5 2026-05-30
RYR17XU Ryanair 5 2026-05-30
RYR981G Ryanair 4 2026-04-16
RYR8QW Ryanair 4 2026-05-19
RYR85AX Ryanair 4 2026-05-20
RYR62BC Ryanair 4 2026-05-20
RYR50DB Ryanair 4 2026-05-16
RYR2AT Ryanair 4 2026-05-19
RYR26NW Ryanair 4 2026-05-19
RYR256T Ryanair 4 2026-05-19
RYR1QK Ryanair 4 2026-05-16
RYR9HD Ryanair 3 2026-04-16
RYR95AT Ryanair 3 2026-05-25
RYR85FH Ryanair 3 2026-05-29
RYR837Z - 3 2026-04-16
RYR6SW Ryanair 3 2026-05-29
RYR5ZL Ryanair 3 2026-05-25
RYR5XF Ryanair 3 2026-04-18
RYR54FN Ryanair 3 2026-05-28
RYR2SN Ryanair 3 2026-04-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 RYR17XU BRI → VCE May 30, 05:35 UTCMay 30, 06:40 UTC1h 5m
2026-05-30 RYR29BC VCE → BRI May 30, 03:45 UTCMay 30, 04:45 UTC1h 0m
2026-05-29 RYR85FH CAG → VCE May 29, 22:00 UTCMay 29, 23:00 UTC1h 0m
2026-05-29 RYR6SW FUE → DUB May 29, 20:00 UTCMay 29, 20:55 UTC55m
2026-05-29 RYR80JR DUB → VCE May 29, 16:50 UTCMay 29, 19:00 UTC2h 10m
2026-05-29 RYR16FR VCE → DUB May 29, 13:25 UTCMay 29, 15:50 UTC2h 25m
2026-05-29 RYR73EJ MAN → VCE May 29, 10:20 UTCMay 29, 12:10 UTC1h 50m
2026-05-29 RYR41VQ VCE → MAN May 29, 07:20 UTCMay 29, 09:25 UTC2h 5m
2026-05-28 RYR5TF DUB → FCO May 28, 20:50 UTCMay 28, 22:05 UTC1h 15m
2026-05-28 RYR9159 VCE → SUF May 28, 19:00 UTCMay 28, 20:10 UTC1h 10m
2026-05-28 RYR6LU NOC → LPL May 28, 15:50 UTCMay 28, 18:00 UTC2h 10m
2026-05-28 RYR7DL DUB → NCE May 28, 12:15 UTCMay 28, 14:35 UTC2h 20m
2026-05-28 RYR85FH CAG → VCE May 28, 09:40 UTCMay 28, 10:40 UTC1h 0m
2026-05-28 RYR6SW FUE → DUB May 28, 07:35 UTCMay 28, 08:35 UTC1h 0m
2026-05-28 RYR29BA BDS → VCE May 28, 05:40 UTCMay 28, 06:45 UTC1h 5m
2026-05-28 RYR54FN VCE → BDS May 28, 03:55 UTCMay 28, 04:55 UTC1h 0m
2026-05-27 RYR83ZV BCN → NYO May 27, 19:20 UTCMay 27, 22:00 UTC2h 40m
2026-05-27 RYR40MN ARN → MLA May 27, 14:55 UTCMay 27, 17:40 UTC2h 45m
2026-05-27 RYR71KE STN → VCE May 27, 12:15 UTCMay 27, 13:55 UTC1h 40m
2026-05-27 RYR8UF CWL → AGP May 27, 09:20 UTCMay 27, 11:15 UTC1h 55m
2026-05-27 RYR59ET PMO → VCE May 27, 07:20 UTCMay 27, 08:25 UTC1h 5m
2026-05-27 RYR1GV NRN → FEZ May 27, 05:09 UTCMay 27, 06:20 UTC1h 10m
2026-05-26 RYR6DB HEL → BGY May 26, 20:54 UTCMay 26, 22:29 UTC1h 35m
2026-05-26 RYR8UF CWL → AGP May 26, 18:14 UTCMay 26, 20:05 UTC1h 50m
2026-05-26 RYR6WA BUD → BRS May 26, 11:20 UTCMay 26, 13:19 UTC2h 0m
2026-05-26 RYR6MZ LIS → VCE May 26, 07:40 UTCMay 26, 09:35 UTC1h 55m
2026-05-26 RYR17XU BRI → VCE May 26, 05:49 UTCMay 26, 06:44 UTC55m
2026-05-26 RYR29BC VCE → BRI May 26, 04:00 UTCMay 26, 05:05 UTC1h 5m
2026-05-25 RYR48TB CTA → VCE May 25, 20:19 UTCMay 25, 21:35 UTC1h 15m
2026-05-25 RYR8MJ VCE → CTA May 25, 18:10 UTCMay 25, 19:30 UTC1h 19m
2026-05-25 RYR5ZL BRI → VCE May 25, 15:40 UTCMay 25, 16:35 UTC55m
2026-05-25 RYR95AT DUB → LPA May 25, 13:40 UTCMay 25, 14:35 UTC55m
2026-05-25 RYR29BA BDS → VCE May 25, 11:25 UTCMay 25, 12:25 UTC1h 0m
2026-05-25 RYR54FN VCE → BDS May 25, 09:35 UTCMay 25, 10:40 UTC1h 5m
2026-05-25 RYR59ET PMO → VCE May 25, 06:35 UTCMay 25, 07:45 UTC1h 10m
2026-05-25 RYR1GV NRN → FEZ May 25, 03:45 UTCMay 25, 04:50 UTC1h 5m
2026-05-24 RYR4LD ALC → PMI May 24, 19:25 UTCMay 24, 20:40 UTC1h 15m
2026-05-24 RYR5ZL BRI → VCE May 24, 16:25 UTCMay 24, 17:20 UTC55m
2026-05-24 RYR95AT DUB → LPA May 24, 14:40 UTCMay 24, 15:40 UTC1h 0m
2026-05-24 RYR73EJ MAN → VCE May 24, 11:30 UTCMay 24, 13:35 UTC2h 5m
2026-05-24 RYR41VQ VCE → MAN May 24, 08:40 UTCMay 24, 10:40 UTC2h 0m
2026-05-24 RYR17XU BRI → VCE May 24, 05:40 UTCMay 24, 06:40 UTC1h 0m
2026-05-24 RYR29BC VCE → BRI May 24, 03:50 UTCMay 24, 04:45 UTC55m
2026-05-23 RYR83ZV BCN → NYO May 23, 20:05 UTCMay 23, 22:35 UTC2h 30m
2026-05-23 RYR40MN ARN → MLA May 23, 16:05 UTCMay 23, 19:00 UTC2h 56m
2026-05-23 RYR63LN VIE → VCE May 23, 14:10 UTCMay 23, 14:50 UTC40m
2026-05-23 RYR93QM - May 23, 12:35 UTCMay 23, 13:20 UTC45m
2026-05-23 RYR2112 WRO → TRF May 23, 10:15 UTCMay 23, 11:15 UTC1h 0m
2026-05-23 RYR8ZF HAM → EDI May 23, 08:10 UTCMay 23, 09:00 UTC50m
2026-05-23 RYR17XU BRI → VCE May 23, 05:45 UTCMay 23, 06:45 UTC1h 0m

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

Mode-S 4D21EF frequently asked

What is Mode-S code 4D21EF?
4D21EF is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-QAG.
Where is Mode-S 4D21EF registered?
Mode-S code 4D21EF is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D21EF broadcasting right now?
Yes. Mode-S 4D21EF is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D21EF, octal 23220757, decimal 5,054,959.
What flights does 4D21EF operate?
Mode-S 4D21EF has broadcast 20 distinct callsigns, including RYR29BC, RYR17XU, RYR981G, RYR8QW, RYR85AX.