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 RYR74XG · 35,000 ft
Flights observed
651
Distinct callsigns
20
Country
MT
Last broadcast
Jul 26, 20:25 UTC

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
RYR6AX Ryanair 4 2026-07-21
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
RYR15RL - 4 2026-07-21
RYR9HD Ryanair 3 2026-04-16
RYR95AT Ryanair 3 2026-05-25
RYR85FH Ryanair 3 2026-05-29
RYR83ZV Ryanair 3 2026-05-30
RYR837Z - 3 2026-04-16
RYR6SW Ryanair 3 2026-05-29
RYR5ZL Ryanair 3 2026-05-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 RYR65RJ ZAG → CRL Jul 26, 18:45 UTCJul 26, 20:25 UTC1h 40m
2026-07-26 RYR5926 - Jul 26, 16:30 UTCJul 26, 17:50 UTC1h 20m
2026-07-26 RYR8AU BZG → STN Jul 26, 13:40 UTCJul 26, 15:35 UTC1h 55m
2026-07-26 RYR36TZ CRL → MAD Jul 26, 10:15 UTCJul 26, 11:55 UTC1h 40m
2026-07-26 RYR7WU EIN → DUB Jul 26, 07:05 UTCJul 26, 08:15 UTC1h 10m
2026-07-26 RYR56DD CRL → TSF Jul 26, 04:50 UTCJul 26, 05:55 UTC1h 5m
2026-07-25 RYR105V BIQ → CRL Jul 25, 18:50 UTCJul 25, 20:15 UTC1h 25m
2026-07-25 RYR92NU - Jul 25, 16:40 UTCJul 25, 17:55 UTC1h 15m
2026-07-25 RYR6FC STN → BER Jul 25, 13:40 UTCJul 25, 15:35 UTC1h 55m
2026-07-25 RYR83BZ CRL → BRI Jul 25, 10:50 UTCJul 25, 12:35 UTC1h 45m
2026-07-25 RYR38SG LIS → BER Jul 25, 07:40 UTCJul 25, 09:55 UTC2h 15m
2026-07-25 RYR2147 CHQ → BHX Jul 25, 05:00 UTCJul 25, 06:55 UTC1h 55m
2026-07-24 RYR8YT EDI → FUE Jul 24, 18:45 UTCJul 24, 21:05 UTC2h 20m
2026-07-24 RYR2DG MAD → VIE Jul 24, 14:45 UTCJul 24, 17:20 UTC2h 35m
2026-07-24 RYR22RD LIS → CRL Jul 24, 11:20 UTCJul 24, 13:25 UTC2h 5m
2026-07-24 RYR3RB BLQ → BRI Jul 24, 07:35 UTCJul 24, 10:10 UTC2h 35m
2026-07-23 RYR53TJ TLS → CRL Jul 23, 18:40 UTCJul 23, 20:00 UTC1h 20m
2026-07-23 RYR8586 - Jul 23, 16:40 UTCJul 23, 17:50 UTC1h 10m
2026-07-23 RYR7LX MAN → PDL Jul 23, 14:40 UTCJul 23, 16:00 UTC1h 20m
2026-07-23 RYR67KN CRL → BLQ Jul 23, 12:40 UTCJul 23, 13:55 UTC1h 15m
2026-07-22 RYR11CL CRL → AGA Jul 22, 18:35 UTCJul 23, 11:15 UTC16h 40m
2026-07-22 RYR99TR AGA → CRL Jul 22, 10:20 UTCJul 22, 17:35 UTC7h 15m
2026-07-21 RYR6AX BVA → AGA Jul 21, 19:45 UTCJul 21, 22:20 UTC2h 35m
2026-07-21 RYR11FB - Jul 21, 16:20 UTCJul 21, 18:45 UTC2h 25m
2026-07-21 RYR15RL - Jul 21, 10:45 UTCJul 21, 14:40 UTC3h 55m
2026-07-20 RYR288Q - Jul 20, 18:10 UTCJul 21, 09:25 UTC15h 14m
2026-07-20 RYR9348 - Jul 20, 09:20 UTCJul 20, 17:10 UTC7h 50m
2026-07-19 RYR8EL - Jul 19, 20:00 UTCJul 20, 08:35 UTC12h 35m
2026-07-19 RYR3273 - Jul 19, 09:35 UTCJul 19, 18:05 UTC8h 30m
2026-07-18 RYR15RL - Jul 18, 19:10 UTCJul 19, 08:25 UTC13h 15m
2026-07-18 RYR31QZ - Jul 18, 14:25 UTCJul 18, 17:45 UTC3h 20m
2026-07-18 RYR46VZ - Jul 18, 09:25 UTCJul 18, 12:20 UTC2h 55m
2026-07-17 RYR8177 WRO → CRL Jul 17, 20:40 UTCJul 18, 08:25 UTC11h 46m
2026-07-17 RYR8176 - Jul 17, 15:10 UTCJul 17, 18:50 UTC3h 40m
2026-07-17 RYR29WH - Jul 17, 10:10 UTCJul 17, 12:25 UTC2h 15m
2026-07-16 RYR6AX - Jul 16, 21:05 UTCJul 17, 08:54 UTC11h 50m
2026-07-16 RYR11FB - Jul 16, 17:20 UTCJul 16, 19:45 UTC2h 25m
2026-07-16 RYR46VZ - Jul 16, 12:09 UTCJul 16, 15:35 UTC3h 25m
2026-07-16 RYR9HF - Jul 16, 08:20 UTCJul 16, 10:59 UTC2h 40m
2026-07-15 RYR11CL - Jul 15, 19:00 UTCJul 15, 22:25 UTC3h 25m
2026-07-15 RYR6AX - Jul 15, 10:15 UTCJul 15, 17:30 UTC7h 15m
2026-07-14 RYR6AX - Jul 14, 20:10 UTCJul 15, 09:15 UTC13h 4m
2026-07-14 RYR15RL - Jul 14, 11:15 UTCJul 14, 19:05 UTC7h 50m
2026-07-13 RYR288Q - Jul 13, 18:15 UTCJul 14, 09:20 UTC15h 5m
2026-07-13 RYR9348 - Jul 13, 09:25 UTCJul 13, 17:15 UTC7h 50m
2026-07-12 RYR8EL - Jul 12, 19:25 UTCJul 13, 08:10 UTC12h 45m
2026-07-12 RYR2358 - Jul 12, 10:05 UTCJul 12, 18:05 UTC8h 0m
2026-07-11 RYR15RL - Jul 11, 20:40 UTCJul 12, 08:30 UTC11h 50m
2026-07-11 RYR8GW BCN → VIE Jul 11, 17:15 UTCJul 11, 19:05 UTC1h 50m
2026-07-11 RYR1GE BCN → BCN Jul 11, 09:55 UTCJul 11, 15:00 UTC5h 5m

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.