sensors Mode-S transponder

4D21C8

ICAO 24-bit transponder address · allocated to Malta

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

Hex
4D21C8
Octal
23220710
Decimal
5,054,920
Country
MT
Tail
9H-TJC
Type
B738
Broadcasting now · callsign CXI4C · 37,000 ft
Flights observed
160
Distinct callsigns
20
Country
MT
Last broadcast
1h ago

Current position

4D21C8 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4D21C8 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
CXI5RU - 12 2026-05-13
SEJ682 - 6 2026-04-22
CXI6HN Shanxi Airlines 6 2026-05-28
SEJ802 Spicejet 5 2026-04-20
SEJ681 Spicejet 5 2026-04-22
SEJ648 Spicejet 5 2026-04-22
SEJ876 Spicejet 4 2026-04-30
SEJ650 - 4 2026-04-30
SEJ647 Spicejet 4 2026-04-22
SEJ642 Spicejet 4 2026-04-28
CXI8DF - 4 2026-05-22
CXI4C Shanxi Airlines 4 2026-05-30
SEJ877 Spicejet 3 2026-04-30
SEJ801 Spicejet 3 2026-04-20
SEJ674 Spicejet 3 2026-04-19
SEJ672 Spicejet 3 2026-04-19
SEJ640 Spicejet 3 2026-04-27
SEJ252 Spicejet 3 2026-04-17
CXI7U Shanxi Airlines 3 2026-05-11
CXI6B Shanxi Airlines 3 2026-05-11

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 CXI4C NUE → HRG May 30, 07:20 UTCMay 30, 08:00 UTC40m
2026-05-29 CXI67FR FUE → DUS May 29, 14:00 UTCMay 29, 17:45 UTC3h 45m
2026-05-29 CXI8AP - May 29, 08:30 UTCMay 29, 12:00 UTC3h 30m
2026-05-28 CXI6HN HRG → DUS May 28, 06:10 UTCMay 28, 16:50 UTC10h 40m
2026-05-27 CXI67FR FUE → DUS May 27, 15:25 UTCMay 27, 18:25 UTC3h 0m
2026-05-27 CXI67FR FUE → DUS May 27, 14:20 UTCMay 27, 14:40 UTC20m
2026-05-27 CXI52RU DUS → FUE May 27, 08:30 UTCMay 27, 11:30 UTC3h 0m
2026-05-26 CXI6HN HRG → DUS May 26, 13:40 UTCMay 26, 17:25 UTC3h 45m
2026-05-26 CXI4C NUE → HRG May 26, 06:29 UTCMay 26, 09:29 UTC3h 0m
2026-05-25 CXI6HN HRG → DUS May 25, 14:45 UTCMay 25, 18:40 UTC3h 55m
2026-05-25 CXI4C NUE → HRG May 25, 07:30 UTCMay 25, 10:35 UTC3h 5m
2026-05-24 CXI6HN HRG → DUS May 24, 14:35 UTCMay 24, 17:40 UTC3h 5m
2026-05-24 CXI6HN HRG → DUS May 24, 13:35 UTCMay 24, 13:50 UTC15m
2026-05-24 CXI4C NUE → HRG May 24, 06:10 UTCMay 24, 09:05 UTC2h 55m
2026-05-23 CXI2CL CFU → DUS May 23, 18:50 UTCMay 23, 21:10 UTC2h 20m
2026-05-23 CXI9N KGS → CGN May 23, 15:05 UTCMay 23, 17:20 UTC2h 15m
2026-05-23 CXI3CA HRG → LEJ May 23, 10:10 UTCMay 23, 13:35 UTC3h 25m
2026-05-23 CXI9NM DUS → RHO May 23, 04:50 UTCMay 23, 08:05 UTC3h 15m
2026-05-22 CXI4HL PMI → DUS May 22, 17:40 UTCMay 22, 19:55 UTC2h 15m
2026-05-22 CXI6F HER → BER May 22, 14:15 UTCMay 22, 16:20 UTC2h 5m
2026-05-22 CXI8DF - May 22, 09:55 UTCMay 22, 12:55 UTC3h 0m
2026-05-22 CXI16QB DUS → HER May 22, 05:10 UTCMay 22, 08:20 UTC3h 10m
2026-05-21 CXI99TK CFU → DUS May 21, 17:55 UTCMay 21, 20:10 UTC2h 15m
2026-05-21 CXI9N KGS → CGN May 21, 14:20 UTCMay 21, 16:25 UTC2h 5m
2026-05-21 CXI8DF - May 21, 09:25 UTCMay 21, 12:30 UTC3h 5m
2026-05-21 CXI8A DUS → HER May 21, 05:00 UTCMay 21, 07:50 UTC2h 50m
2026-05-20 CXI6HN HRG → DUS May 20, 06:20 UTCMay 20, 16:50 UTC10h 30m
2026-05-19 CXI8DF - May 19, 15:40 UTCMay 19, 18:35 UTC2h 55m
2026-05-19 CXI4PL DUS → HER May 19, 11:25 UTCMay 19, 14:10 UTC2h 45m
2026-05-19 CXI74KH HER → DUS May 19, 05:30 UTCMay 19, 08:30 UTC3h 0m
2026-05-19 CXI7FT NUE → HER May 19, 01:25 UTCMay 19, 03:45 UTC2h 20m
2026-05-18 CXI7PV HER → NUE May 18, 21:35 UTCMay 19, 00:05 UTC2h 30m
2026-05-18 CXI8DE DUS → HER May 18, 17:30 UTCMay 18, 20:15 UTC2h 44m
2026-05-18 CXI8DF - May 18, 13:15 UTCMay 18, 16:20 UTC3h 5m
2026-05-17 CXI6DP GRQ → HER May 17, 19:45 UTCMay 17, 22:45 UTC3h 0m
2026-05-17 CXI21DG HER → GRQ May 17, 15:15 UTCMay 17, 18:25 UTC3h 10m
2026-05-17 CXI1T LGW → HER May 17, 10:05 UTCMay 17, 13:20 UTC3h 15m
2026-05-17 CXI33RE HER → LGW May 17, 04:55 UTCMay 17, 08:40 UTC3h 45m
2026-05-16 CXI59YU KTW → HER May 16, 17:05 UTCMay 16, 19:15 UTC2h 10m
2026-05-16 CXI8CE - May 16, 13:35 UTCMay 16, 15:55 UTC2h 20m
2026-05-16 CXI39TX WAW → HER May 16, 09:31 UTCMay 16, 12:01 UTC2h 30m
2026-05-16 CXI37FZ HER → WAW May 16, 05:20 UTCMay 16, 07:55 UTC2h 36m
2026-05-16 CXI9X CGN → RHO May 16, 01:05 UTCMay 16, 03:40 UTC2h 35m
2026-05-15 CXI7F HER → HAJ May 15, 20:45 UTCMay 15, 23:45 UTC3h 0m
2026-05-15 CXI8T CGN → HER May 15, 10:15 UTCMay 15, 12:50 UTC2h 35m
2026-05-15 CXI8E NUE → NUE May 15, 05:55 UTCMay 15, 08:45 UTC2h 50m
2026-05-15 CXI6GB FMO → HER May 15, 01:40 UTCMay 15, 04:20 UTC2h 40m
2026-05-14 CXI2R LPA → NUE May 14, 21:10 UTCMay 15, 00:25 UTC3h 15m
2026-05-14 CXI6DP GRQ → HER May 14, 16:50 UTCMay 14, 19:35 UTC2h 45m
2026-05-14 CXI1PJ HER → GRQ May 14, 12:20 UTCMay 14, 15:30 UTC3h 10m

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

Mode-S 4D21C8 frequently asked

What is Mode-S code 4D21C8?
4D21C8 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-TJC.
Where is Mode-S 4D21C8 registered?
Mode-S code 4D21C8 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D21C8 broadcasting right now?
Yes. Mode-S 4D21C8 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D21C8, octal 23220710, decimal 5,054,920.
What flights does 4D21C8 operate?
Mode-S 4D21C8 has broadcast 20 distinct callsigns, including CXI5RU, SEJ682, CXI6HN, SEJ802, SEJ681.