sensors Mode-S transponder

4D2191

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-OJJ · BOMBARDIER CL-600 Challenger

Hex
4D2191
Octal
23220621
Decimal
5,054,865
Country
MT
Tail
9H-OJJ
Type
CL60
No current signal · last broadcast 1d ago
Flights observed
42
Distinct callsigns
1
Country
MT
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4D2191.

Country allocation

The ICAO 24-bit address 4D2191 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 1 distinct

Callsign Airline Flights Last seen
ULC7P - 42 2026-05-28

Recent flights last 42

DateFlightRouteTakeoffLandingDuration
2026-05-28 ULC7P - May 28, 19:50 UTCMay 28, 21:45 UTC1h 55m
2026-05-27 ULC7P - May 27, 10:00 UTCMay 27, 10:25 UTC25m
2026-05-27 ULC7P - May 27, 07:50 UTCMay 27, 09:05 UTC1h 15m
2026-05-26 ULC7P - May 26, 13:19 UTCMay 26, 14:05 UTC45m
2026-05-26 ULC7P - May 26, 09:35 UTCMay 26, 10:25 UTC50m
2026-05-26 ULC7P - May 26, 06:54 UTCMay 26, 08:10 UTC1h 15m
2026-05-24 ULC7P - May 24, 16:30 UTCMay 24, 17:40 UTC1h 10m
2026-05-24 ULC7P - May 24, 13:50 UTCMay 24, 15:45 UTC1h 55m
2026-05-24 ULC7P - May 24, 11:30 UTCMay 24, 11:50 UTC20m
2026-05-21 ULC7P - May 21, 11:55 UTCMay 21, 12:20 UTC25m
2026-05-21 ULC7P - May 21, 08:45 UTCMay 21, 10:25 UTC1h 40m
2026-05-21 ULC7P - May 21, 07:10 UTCMay 21, 07:45 UTC35m
2026-05-20 ULC7P - May 20, 11:30 UTCMay 20, 14:00 UTC2h 30m
2026-05-20 ULC7P - May 20, 06:10 UTCMay 20, 07:45 UTC1h 35m
2026-05-19 ULC7P POZ → WAW May 19, 06:05 UTCMay 19, 06:45 UTC40m
2026-05-18 ULC7P - May 18, 07:10 UTCMay 18, 08:45 UTC1h 35m
2026-05-17 ULC7P - May 17, 09:30 UTCMay 17, 10:45 UTC1h 15m
2026-05-17 ULC7P - May 17, 07:10 UTCMay 17, 08:25 UTC1h 15m
2026-05-14 ULC7P - May 14, 10:35 UTCMay 14, 11:50 UTC1h 15m
2026-05-14 ULC7P - May 14, 08:00 UTCMay 14, 09:15 UTC1h 15m
2026-05-14 ULC7P - May 14, 05:40 UTCMay 14, 07:20 UTC1h 40m
2026-05-12 ULC7P LCY → POZ May 12, 16:35 UTCMay 12, 18:15 UTC1h 40m
2026-05-12 ULC7P - May 12, 07:10 UTCMay 12, 08:35 UTC1h 25m
2026-05-11 ULC7P - May 11, 06:50 UTCMay 11, 07:55 UTC1h 5m
2026-05-10 ULC7P - May 10, 10:05 UTCMay 10, 11:15 UTC1h 10m
2026-05-07 ULC7P - May 7, 09:30 UTCMay 7, 10:55 UTC1h 25m
2026-05-07 ULC7P - May 7, 07:20 UTCMay 7, 08:30 UTC1h 10m
2026-05-06 ULC7P - May 6, 10:45 UTCMay 6, 12:40 UTC1h 55m
2026-05-04 ULC7P - May 4, 14:40 UTCMay 4, 16:25 UTC1h 45m
2026-05-03 ULC7P - May 3, 10:45 UTCMay 3, 12:00 UTC1h 15m
2026-04-30 ULC7P - Apr 30, 09:05 UTCApr 30, 10:20 UTC1h 15m
2026-04-29 ULC7P NHT → GVA Apr 29, 18:05 UTCApr 29, 19:35 UTC1h 30m
2026-04-27 ULC7P - Apr 27, 08:00 UTCApr 27, 09:25 UTC1h 25m
2026-04-24 ULC7P - Apr 24, 17:35 UTCApr 24, 19:35 UTC2h 0m
2026-04-23 ULC7P ZRH → WAW Apr 23, 09:50 UTCApr 23, 11:40 UTC1h 50m
2026-04-22 ULC7P - Apr 22, 17:45 UTCApr 22, 18:35 UTC50m
2026-04-22 ULC7P - Apr 22, 12:30 UTCApr 22, 13:05 UTC35m
2026-04-21 ULC7P POZ → ZRH Apr 21, 13:55 UTCApr 21, 15:15 UTC1h 20m
2026-04-20 ULC7P - Apr 20, 07:10 UTCApr 20, 08:50 UTC1h 40m
2026-04-15 ULC7P - Apr 15, 15:05 UTCApr 15, 15:55 UTC50m
2026-04-15 ULC7P - Apr 15, 14:15 UTCApr 15, 14:55 UTC39m
2026-04-14 ULC7P - Apr 14, 07:10 UTCApr 14, 08:45 UTC1h 35m

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

Mode-S 4D2191 frequently asked

What is Mode-S code 4D2191?
4D2191 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-OJJ.
Where is Mode-S 4D2191 registered?
Mode-S code 4D2191 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D2191 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2191, octal 23220621, decimal 5,054,865.
What flights does 4D2191 operate?
Mode-S 4D2191 has broadcast 1 distinct callsign, including ULC7P.