Apparatus

Try JFK, AAL1290, BAW, or N225AN.

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 Jul 26, 12:55 UTC
Flights observed
120
Distinct callsigns
2
Country
MT
Last broadcast
Jul 26, 12:55 UTC

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 2 distinct

Callsign Airline Flights Last seen
ULC7P - 118 2026-07-26
9HJAAL - 2 2026-07-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ULC7P NCE → BUD Jul 26, 11:20 UTCJul 26, 12:50 UTC1h 30m
2026-07-25 9HJAAL - Jul 25, 14:00 UTCJul 25, 14:55 UTC55m
2026-07-25 ULC7P - Jul 25, 12:20 UTCJul 25, 13:05 UTC45m
2026-07-25 ULC7P - Jul 25, 08:25 UTCJul 25, 09:45 UTC1h 20m
2026-07-25 ULC7P - Jul 25, 06:05 UTCJul 25, 07:10 UTC1h 5m
2026-07-24 ULC7P - Jul 24, 11:40 UTCJul 24, 13:00 UTC1h 20m
2026-07-24 ULC7P - Jul 24, 10:05 UTCJul 24, 10:30 UTC25m
2026-07-24 ULC7P - Jul 24, 07:20 UTCJul 24, 08:10 UTC50m
2026-07-23 ULC7P - Jul 23, 12:55 UTCJul 23, 13:45 UTC50m
2026-07-23 ULC7P GVA → LUX Jul 23, 10:55 UTCJul 23, 11:40 UTC45m
2026-07-18 ULC7P - Jul 18, 19:15 UTCJul 18, 21:10 UTC1h 55m
2026-07-18 ULC7P - Jul 18, 15:35 UTCJul 18, 17:40 UTC2h 5m
2026-07-18 ULC7P - Jul 18, 12:15 UTCJul 18, 13:20 UTC1h 5m
2026-07-18 ULC7P - Jul 18, 09:45 UTCJul 18, 10:30 UTC45m
2026-07-17 ULC7P - Jul 17, 15:35 UTCJul 17, 16:29 UTC55m
2026-07-17 ULC7P - Jul 17, 14:04 UTCJul 17, 14:55 UTC50m
2026-07-16 ULC7P POZ → GVA Jul 16, 11:34 UTCJul 16, 13:20 UTC1h 45m
2026-07-14 ULC7P - Jul 14, 10:05 UTCJul 14, 10:40 UTC35m
2026-07-14 ULC7P - Jul 14, 08:35 UTCJul 14, 09:10 UTC35m
2026-07-14 ULC7P - Jul 14, 06:10 UTCJul 14, 07:45 UTC1h 35m
2026-07-12 ULC7P - Jul 12, 14:55 UTCJul 12, 16:01 UTC1h 5m
2026-07-12 ULC7P - Jul 12, 11:40 UTCJul 12, 12:25 UTC45m
2026-07-11 ULC7P - Jul 11, 12:55 UTCJul 11, 14:45 UTC1h 50m
2026-07-11 ULC7P - Jul 11, 08:55 UTCJul 11, 10:45 UTC1h 50m
2026-07-10 ULC7P - Jul 10, 16:50 UTCJul 10, 18:00 UTC1h 10m
2026-07-10 ULC7P - Jul 10, 14:20 UTCJul 10, 16:05 UTC1h 45m
2026-07-10 ULC7P - Jul 10, 09:25 UTCJul 10, 11:05 UTC1h 40m
2026-07-10 ULC7P - Jul 10, 07:20 UTCJul 10, 08:05 UTC45m
2026-07-05 ULC7P - Jul 5, 15:40 UTCJul 5, 16:20 UTC40m
2026-07-04 ULC7P - Jul 4, 14:50 UTCJul 4, 15:55 UTC1h 5m
2026-07-04 ULC7P - Jul 4, 12:10 UTCJul 4, 13:15 UTC1h 5m
2026-07-04 9HJAAL - Jul 4, 09:50 UTCJul 4, 10:50 UTC1h 0m
2026-07-03 ULC7P - Jul 3, 13:00 UTCJul 3, 13:20 UTC20m
2026-07-03 ULC7P - Jul 3, 10:55 UTCJul 3, 11:50 UTC55m
2026-06-30 ULC7P - Jun 30, 18:25 UTCJun 30, 19:30 UTC1h 5m
2026-06-30 ULC7P - Jun 30, 14:35 UTCJun 30, 16:50 UTC2h 15m
2026-06-29 ULC7P VIE → WAW Jun 29, 12:34 UTCJun 29, 13:30 UTC55m
2026-06-29 ULC7P - Jun 29, 10:10 UTCJun 29, 11:04 UTC55m
2026-06-29 ULC7P - Jun 29, 06:29 UTCJun 29, 08:39 UTC2h 10m
2026-06-28 ULC7P - Jun 28, 17:04 UTCJun 28, 17:30 UTC25m
2026-06-28 ULC7P - Jun 28, 09:05 UTCJun 28, 09:45 UTC40m
2026-06-27 ULC7P - Jun 27, 13:44 UTCJun 27, 14:20 UTC35m
2026-06-27 ULC7P - Jun 27, 11:14 UTCJun 27, 12:09 UTC55m
2026-06-25 ULC7P - Jun 25, 15:29 UTCJun 25, 16:05 UTC35m
2026-06-25 ULC7P - Jun 25, 13:24 UTCJun 25, 14:50 UTC1h 25m
2026-06-25 ULC7P - Jun 25, 11:25 UTCJun 25, 12:35 UTC1h 10m
2026-06-24 ULC7P - Jun 24, 17:10 UTCJun 24, 19:10 UTC2h 0m
2026-06-22 ULC7P GVA → WAW Jun 22, 05:04 UTCJun 22, 07:00 UTC1h 55m
2026-06-21 ULC7P - Jun 21, 10:29 UTCJun 21, 11:55 UTC1h 25m
2026-06-20 ULC7P - Jun 20, 15:49 UTCJun 20, 18:10 UTC2h 20m

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 Jul 26, 12:55 UTC.
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 2 distinct callsigns, including ULC7P, 9HJAAL.