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sensors Mode-S transponder

4D23C4

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-VDC · AIRBUS A-330-300

Hex
4D23C4
Octal
23221704
Decimal
5,055,428
Country
MT
Tail
9H-VDC
Type
A333
No current signal · last broadcast Jul 26, 21:35 UTC
Flights observed
147
Distinct callsigns
20
Country
MT
Last broadcast
Jul 26, 21:35 UTC

Last known position

Most recent position reported by Mode-S 4D23C4.

Country allocation

The ICAO 24-bit address 4D23C4 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
GTR1986 - 16 2026-07-24
GTR1604 - 12 2026-07-13
GTR1975 - 11 2026-07-23
GTR1956 - 10 2026-07-25
GTR1914 - 8 2026-05-02
GTR1573 - 8 2026-05-03
GTR1568 Gestar 7 2026-05-23
GTR1924 - 6 2026-05-26
GTR1560 Gestar 6 2026-05-24
GTR1515 - 6 2026-05-25
GTR1926 - 5 2026-05-26
GTR1538 - 5 2026-05-27
GTR1962 - 4 2026-05-02
GTR1563 - 4 2026-07-26
GTR1530 - 4 2026-07-15
GTR1932 Gestar 3 2026-05-14
GTR1566 Gestar 3 2026-05-23
GTR1977 - 2 2026-07-12
GTR1945 - 2 2026-04-29
GTR1912 - 2 2026-07-21

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 GTR1563 TBS → ZAZ Jul 26, 16:25 UTCJul 26, 21:35 UTC5h 10m
2026-07-26 GTR1563 - Jul 26, 08:30 UTCJul 26, 14:05 UTC5h 35m
2026-07-25 GTR1554 - Jul 25, 17:40 UTCJul 26, 05:20 UTC11h 40m
2026-07-25 GTR1956 - Jul 25, 12:40 UTCJul 25, 14:40 UTC2h 0m
2026-07-25 GTR1956 - Jul 25, 02:25 UTCJul 25, 10:50 UTC8h 25m
2026-07-24 GTR1986 - Jul 24, 09:10 UTCJul 24, 14:45 UTC5h 35m
2026-07-23 GTR1986 - Jul 23, 17:05 UTCJul 24, 14:45 UTC21h 40m
2026-07-23 GTR1986 - Jul 23, 15:45 UTCJul 24, 14:45 UTC23h 0m
2026-07-23 GTR1975 - Jul 23, 12:05 UTCJul 24, 11:00 UTC22h 55m
2026-07-22 GTR1975 - Jul 22, 15:15 UTCJul 22, 19:00 UTC3h 45m
2026-07-22 GTR1513 - Jul 22, 10:20 UTCJul 22, 13:05 UTC2h 45m
2026-07-21 GTR1513 DAC → TBS Jul 21, 23:05 UTCJul 22, 05:05 UTC6h 0m
2026-07-21 GTR1519 - Jul 21, 08:20 UTCJul 21, 20:10 UTC11h 50m
2026-07-21 GTR1912 - Jul 21, 00:10 UTCJul 21, 05:45 UTC5h 35m
2026-07-20 GTR1912 - Jul 20, 17:25 UTCJul 20, 21:50 UTC4h 25m
2026-07-18 GTR1563 - Jul 18, 03:00 UTCJul 18, 19:35 UTC16h 35m
2026-07-17 GTR1552 ZAZ → DEL Jul 17, 09:20 UTCJul 18, 00:29 UTC15h 10m
2026-07-16 GTR1948 - Jul 16, 00:40 UTCJul 16, 14:35 UTC13h 55m
2026-07-15 GTR1530 TBS → ZAZ Jul 15, 16:25 UTCJul 15, 21:35 UTC5h 10m
2026-07-15 GTR1530 - Jul 15, 08:55 UTCJul 15, 14:35 UTC5h 40m
2026-07-14 GTR1529 - Jul 14, 17:05 UTCJul 15, 05:20 UTC12h 14m
2026-07-14 GTR1526 - Jul 14, 02:35 UTCJul 14, 14:30 UTC11h 55m
2026-07-13 GTR1604 - Jul 13, 21:30 UTCJul 14, 00:45 UTC3h 15m
2026-07-13 GTR1604 - Jul 13, 16:20 UTCJul 13, 19:45 UTC3h 25m
2026-07-13 GTR1604 - Jul 13, 09:10 UTCJul 13, 12:30 UTC3h 20m
2026-07-13 GTR1578 TBS → ZAZ Jul 13, 00:45 UTCJul 13, 05:55 UTC5h 10m
2026-07-12 GTR1578 - Jul 12, 16:20 UTCJul 12, 22:25 UTC6h 5m
2026-07-12 GTR1977 - Jul 12, 04:50 UTCJul 12, 14:25 UTC9h 35m
2026-07-11 GTR1977 - Jul 11, 23:50 UTCJul 12, 03:15 UTC3h 25m
2026-07-11 GTR1563 - Jul 11, 03:15 UTCJul 11, 21:40 UTC18h 25m
2026-07-10 GTR1552 - Jul 10, 09:30 UTCJul 11, 00:25 UTC14h 55m
2026-07-08 GTR1530 TBS → ZAZ Jul 8, 15:00 UTCJul 8, 20:05 UTC5h 5m
2026-07-08 GTR1530 - Jul 8, 06:25 UTCJul 8, 12:30 UTC6h 5m
2026-07-07 GTR1526 - Jul 7, 09:45 UTCJul 8, 04:00 UTC18h 15m
2026-07-06 GTR1604 - Jul 6, 21:45 UTCJul 7, 05:50 UTC8h 5m
2026-07-06 GTR1604 - Jul 6, 14:30 UTCJul 6, 17:55 UTC3h 25m
2026-07-06 GTR1986 - Jul 6, 05:00 UTCJul 6, 10:35 UTC5h 35m
2026-07-05 GTR1986 - Jul 5, 11:20 UTCJul 6, 10:35 UTC23h 15m
2026-07-05 GTR1986 - Jul 5, 09:10 UTCJul 6, 09:00 UTC23h 50m
2026-07-05 GTR1975 - Jul 5, 07:45 UTCJul 5, 13:15 UTC5h 30m
2026-07-04 GTR1975 - Jul 4, 23:00 UTCJul 5, 06:00 UTC7h 0m
2026-07-04 GTR9533 - Jul 4, 20:10 UTCJul 4, 20:50 UTC40m
2026-07-03 GTR9532 - Jul 3, 02:40 UTCJul 3, 03:25 UTC45m
2026-07-02 GTR1548 TBS → ZAZ Jul 2, 17:25 UTCJul 2, 22:20 UTC4h 55m
2026-07-02 GTR1548 - Jul 2, 09:15 UTCJul 2, 15:10 UTC5h 55m
2026-07-02 GTR1937 - Jul 2, 02:35 UTCJul 2, 07:15 UTC4h 40m
2026-07-01 GTR1935 - Jul 1, 15:45 UTCJul 1, 23:00 UTC7h 15m
2026-07-01 GTR9531 - Jul 1, 09:20 UTCJul 1, 10:05 UTC45m
2026-06-01 GTR9510 - Jun 1, 15:10 UTCJun 1, 16:00 UTC50m
2026-05-28 GTR1986 - May 28, 21:15 UTCMay 29, 02:45 UTC5h 30m

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

Mode-S 4D23C4 frequently asked

What is Mode-S code 4D23C4?
4D23C4 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-VDC.
Where is Mode-S 4D23C4 registered?
Mode-S code 4D23C4 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D23C4 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:35 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D23C4, octal 23221704, decimal 5,055,428.
What flights does 4D23C4 operate?
Mode-S 4D23C4 has broadcast 20 distinct callsigns, including GTR1986, GTR1604, GTR1975, GTR1956, GTR1914.