sensors Mode-S transponder

4D23FC

ICAO 24-bit transponder address · allocated to Malta

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

Hex
4D23FC
Octal
23221774
Decimal
5,055,484
Country
MT
Tail
9H-QET
Type
B738
Photo of 9H-QET
Broadcasting now · callsign RYR9525 · 36,525 ft
Flights observed
15
Distinct callsigns
10
Country
MT
Last broadcast
12h ago

Current position

4D23FC is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D23FC 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 10 distinct

Callsign Airline Flights Last seen
RYR76FJ - 2 2026-04-14
RYR5687 - 2 2026-04-13
RYR51VL - 2 2026-04-13
RYR2SR - 2 2026-04-13
RYR2LM - 2 2026-04-13
RYR87YL Ryanair 1 2026-04-13
RYR82SQ - 1 2026-04-14
RYR755H - 1 2026-04-12
RYR687J - 1 2026-04-12
RYR5DF - 1 2026-04-13

Recent flights last 15

DateFlightRouteTakeoffLandingDuration
2026-04-14 RYR76FJ - Apr 14, 09:10 UTCApr 14, 10:30 UTC1h 20m
2026-04-14 RYR76FJ - Apr 14, 08:25 UTCApr 14, 09:05 UTC40m
2026-04-14 RYR82SQ - Apr 14, 05:15 UTCApr 14, 06:35 UTC1h 20m
2026-04-13 RYR2LM - Apr 13, 19:50 UTCApr 13, 20:15 UTC25m
2026-04-13 RYR2LM - Apr 13, 17:25 UTCApr 13, 20:10 UTC2h 45m
2026-04-13 RYR2SR - Apr 13, 15:50 UTCApr 13, 16:15 UTC25m
2026-04-13 RYR2SR - Apr 13, 13:35 UTCApr 13, 16:15 UTC2h 40m
2026-04-13 RYR5687 - Apr 13, 11:55 UTCApr 13, 12:25 UTC30m
2026-04-13 RYR5687 - Apr 13, 11:10 UTCApr 13, 12:15 UTC1h 5m
2026-04-13 RYR5DF - Apr 13, 08:55 UTCApr 13, 10:10 UTC1h 15m
2026-04-13 RYR51VL - Apr 13, 07:55 UTCApr 13, 08:05 UTC10m
2026-04-13 RYR51VL - Apr 13, 06:45 UTCApr 13, 08:05 UTC1h 20m
2026-04-13 RYR87YL ALC → GDN Apr 13, 04:25 UTCApr 13, 05:55 UTC1h 30m
2026-04-12 RYR755H - Apr 12, 18:45 UTCApr 12, 20:15 UTC1h 30m
2026-04-12 RYR687J - Apr 12, 17:15 UTCApr 12, 17:55 UTC40m

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

Mode-S 4D23FC frequently asked

What is Mode-S code 4D23FC?
4D23FC is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-QET.
Where is Mode-S 4D23FC registered?
Mode-S code 4D23FC is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D23FC broadcasting right now?
Yes. Mode-S 4D23FC is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D23FC, octal 23221774, decimal 5,055,484.
What flights does 4D23FC operate?
Mode-S 4D23FC has broadcast 10 distinct callsigns, including RYR76FJ, RYR5687, RYR51VL, RYR2SR, RYR2LM.