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sensors Mode-S transponder

4D23EF

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-PET · DE HAVILLAND DHC-8-400 Dash 8

Hex
4D23EF
Octal
23221757
Decimal
5,055,471
Country
MT
Tail
9H-PET
Type
DH8D
Broadcasting now · callsign SWU1954 · 24,000 ft
Flights observed
146
Distinct callsigns
20
Country
MT
Last broadcast
1h ago

Current position

4D23EF is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D23EF 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
SWU1910 - 9 2026-06-27
SWU1911 - 8 2026-06-27
SWU1951 Swiss European Air Lines 7 2026-06-28
SWU1950 - 7 2026-06-28
SWU1907 Swiss European Air Lines 7 2026-06-26
SWU1906 - 7 2026-06-26
SWU1955 Swiss European Air Lines 6 2026-06-25
SWU1954 Swiss European Air Lines 6 2026-06-25
SWU1953 - 6 2026-06-30
SWU1952 - 6 2026-06-30
SWU1957 - 4 2026-06-15
SWU1956 Swiss European Air Lines 4 2026-06-15
SWU1933 Swiss European Air Lines 4 2026-06-21
SWU1932 Swiss European Air Lines 4 2026-06-21
SWU2382 Swiss European Air Lines 3 2026-06-27
SWU2381 Swiss European Air Lines 3 2026-06-26
SWU2380 Swiss European Air Lines 3 2026-06-26
SWU1981 Swiss European Air Lines 3 2026-06-15
SWU1980 Swiss European Air Lines 3 2026-06-15
SWU1941 Swiss European Air Lines 3 2026-06-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-30 SWU1953 - Jun 30, 11:30 UTCJun 30, 12:50 UTC1h 20m
2026-06-30 SWU1952 - Jun 30, 08:20 UTCJun 30, 09:55 UTC1h 35m
2026-06-29 SWU901 - Jun 29, 16:59 UTCJun 29, 17:19 UTC20m
2026-06-29 SWU1988 OMO → BGY Jun 29, 14:44 UTCJun 29, 15:39 UTC55m
2026-06-29 SWU1979 PMO → OMO Jun 29, 12:34 UTCJun 29, 13:44 UTC1h 10m
2026-06-29 SWU1978 - Jun 29, 10:29 UTCJun 29, 11:39 UTC1h 10m
2026-06-29 SWU1989 - Jun 29, 08:19 UTCJun 29, 09:25 UTC1h 5m
2026-06-29 SWU601 BGY → BZO Jun 29, 06:54 UTCJun 29, 07:20 UTC25m
2026-06-28 SWU1953 - Jun 28, 20:09 UTCJun 28, 21:40 UTC1h 30m
2026-06-28 SWU1952 - Jun 28, 18:10 UTCJun 28, 19:29 UTC1h 20m
2026-06-28 SWU1951 BER → BZO Jun 28, 15:09 UTCJun 28, 16:45 UTC1h 35m
2026-06-28 SWU1950 - Jun 28, 12:25 UTCJun 28, 13:59 UTC1h 35m
2026-06-28 SWU1909 - Jun 28, 09:30 UTCJun 28, 11:14 UTC1h 45m
2026-06-28 SWU1908 - Jun 28, 05:55 UTCJun 28, 07:40 UTC1h 45m
2026-06-27 SWU1911 - Jun 27, 14:49 UTCJun 27, 16:14 UTC1h 25m
2026-06-27 SWU2382 CAG → BRN Jun 27, 09:34 UTCJun 27, 09:44 UTC10m
2026-06-27 SWU1910 - Jun 27, 07:15 UTCJun 27, 08:29 UTC1h 15m
2026-06-26 SWU1941 CFU → BZO Jun 26, 18:44 UTCJun 26, 20:15 UTC1h 30m
2026-06-26 SWU1940 BZO → CFU Jun 26, 15:20 UTCJun 26, 16:54 UTC1h 35m
2026-06-26 SWU1907 OLB → BZO Jun 26, 13:04 UTCJun 26, 14:19 UTC1h 15m
2026-06-26 SWU2381 BRN → OLB Jun 26, 10:39 UTCJun 26, 12:00 UTC1h 20m
2026-06-26 SWU2380 OLB → BRN Jun 26, 08:00 UTCJun 26, 09:24 UTC1h 25m
2026-06-26 SWU1906 - Jun 26, 05:35 UTCJun 26, 06:50 UTC1h 15m
2026-06-25 SWU1955 HAM → BZO Jun 25, 15:54 UTCJun 25, 17:25 UTC1h 30m
2026-06-25 SWU1954 BZO → HAM Jun 25, 13:09 UTCJun 25, 14:39 UTC1h 30m
2026-06-25 SWU1964 ANR → BZO Jun 25, 10:35 UTCJun 25, 12:10 UTC1h 35m
2026-06-25 SWU1963 - Jun 25, 07:59 UTCJun 25, 09:34 UTC1h 35m
2026-06-24 SWU1907 OLB → BZO Jun 24, 16:24 UTCJun 24, 17:45 UTC1h 20m
2026-06-24 SWU1906 - Jun 24, 14:15 UTCJun 24, 15:29 UTC1h 15m
2026-06-24 SWU1911 - Jun 24, 08:55 UTCJun 24, 10:25 UTC1h 30m
2026-06-24 SWU1910 - Jun 24, 06:15 UTCJun 24, 07:40 UTC1h 25m
2026-06-23 SWU1955 HAM → BZO Jun 23, 16:09 UTCJun 23, 17:39 UTC1h 30m
2026-06-23 SWU1954 BZO → HAM Jun 23, 13:29 UTCJun 23, 15:04 UTC1h 35m
2026-06-23 SWU1953 - Jun 23, 10:39 UTCJun 23, 11:54 UTC1h 15m
2026-06-23 SWU1952 - Jun 23, 08:15 UTCJun 23, 09:40 UTC1h 25m
2026-06-21 SWU1911 CAG → BZO Jun 21, 19:20 UTCJun 21, 20:45 UTC1h 25m
2026-06-21 SWU1910 - Jun 21, 16:44 UTCJun 21, 18:04 UTC1h 20m
2026-06-21 SWU1933 LGW → BZO Jun 21, 13:29 UTCJun 21, 15:34 UTC2h 5m
2026-06-21 SWU1932 BZO → LGW Jun 21, 09:44 UTCJun 21, 12:14 UTC2h 30m
2026-06-20 SWU602 - Jun 20, 18:19 UTCJun 20, 18:54 UTC35m
2026-06-20 SWU2382 CAG → BRN Jun 20, 09:09 UTCJun 20, 10:49 UTC1h 40m
2026-06-20 SWU1910 - Jun 20, 06:19 UTCJun 20, 07:44 UTC1h 25m
2026-06-19 SWU1937 SKG → BZO Jun 19, 17:44 UTCJun 19, 19:34 UTC1h 50m
2026-06-19 SWU1936 - Jun 19, 14:44 UTCJun 19, 16:44 UTC2h 0m
2026-06-19 SWU1907 OLB → BZO Jun 19, 12:34 UTCJun 19, 13:34 UTC1h 0m
2026-06-19 SWU2381 BRN → OLB Jun 19, 09:59 UTCJun 19, 11:30 UTC1h 30m
2026-06-19 SWU2380 OLB → BRN Jun 19, 07:34 UTCJun 19, 08:54 UTC1h 20m
2026-06-19 SWU1906 BZO → OLB Jun 19, 05:34 UTCJun 19, 06:39 UTC1h 5m
2026-06-18 SWU1903 - Jun 18, 16:00 UTCJun 18, 17:35 UTC1h 35m
2026-06-18 SWU1902 - Jun 18, 13:25 UTCJun 18, 15:10 UTC1h 45m

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

Mode-S 4D23EF frequently asked

What is Mode-S code 4D23EF?
4D23EF is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-PET.
Where is Mode-S 4D23EF registered?
Mode-S code 4D23EF is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D23EF broadcasting right now?
Yes. Mode-S 4D23EF is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D23EF, octal 23221757, decimal 5,055,471.
What flights does 4D23EF operate?
Mode-S 4D23EF has broadcast 20 distinct callsigns, including SWU1910, SWU1911, SWU1951, SWU1950, SWU1907.