sensors Mode-S transponder

50591B

ICAO 24-bit transponder address

Hex
50591B
Octal
24054433
Decimal
5,265,691
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
1
Country
-
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 50591B.

Callsign history 1 distinct

Callsign Airline Flights Last seen
OMM390 - 5 2026-06-24

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-24 OMM390 - Jun 24, 12:04 UTCJun 24, 12:40 UTC35m
2026-06-19 OMM390 - Jun 19, 13:29 UTCJun 19, 14:04 UTC35m
2026-06-19 OMM390 - Jun 19, 07:45 UTCJun 19, 08:24 UTC40m
2026-06-14 OMM390 - Jun 14, 12:25 UTCJun 14, 14:05 UTC1h 40m
2026-06-14 OMM390 - Jun 14, 10:00 UTCJun 14, 11:15 UTC1h 15m

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.

Mode-S 50591B frequently asked

What is Mode-S code 50591B?
50591B is an ICAO 24-bit transponder address.
Is 50591B broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 50591B, octal 24054433, decimal 5,265,691.
What flights does 50591B operate?
Mode-S 50591B has broadcast 1 distinct callsign, including OMM390.