sensors Mode-S transponder

4B839C

ICAO 24-bit transponder address · allocated to Turkey

Currently assigned to KLH71 · BOMBARDIER CL-600 Challenger

Hex
4B839C
Octal
22701634
Decimal
4,948,892
Country
TR
Tail
KLH71
Type
CL60
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
1
Country
TR
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 4B839C.

Country allocation

The ICAO 24-bit address 4B839C falls within the block assigned to Turkey (TR) by ICAO Annex 10, Volume III. Every aircraft registered in Turkey 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
KLH71 - 5 2026-05-07

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-07 KLH71 - May 7, 10:05 UTCMay 7, 10:20 UTC15m
2026-05-07 KLH71 - May 7, 08:35 UTCMay 7, 09:15 UTC40m
2026-05-07 KLH71 - May 7, 07:40 UTCMay 7, 08:00 UTC20m
2026-04-28 KLH71 - Apr 28, 07:40 UTCApr 28, 07:55 UTC15m
2026-04-22 KLH71 - Apr 22, 09:40 UTCApr 22, 09:55 UTC15m

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 KLH71 page for operator, model, and routing details .

Mode-S 4B839C frequently asked

What is Mode-S code 4B839C?
4B839C is an ICAO 24-bit transponder address. Allocated to Turkey. Assigned to KLH71.
Where is Mode-S 4B839C registered?
Mode-S code 4B839C is allocated to Turkey (TR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B839C 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 4B839C, octal 22701634, decimal 4,948,892.
What flights does 4B839C operate?
Mode-S 4B839C has broadcast 1 distinct callsign, including KLH71.