sensors Mode-S transponder

49D423

ICAO 24-bit transponder address · allocated to Czech Republic

Currently assigned to OK-SWM · BOEING 737 MAX 8

Hex
49D423
Octal
22352043
Decimal
4,838,435
Country
CZ
Tail
OK-SWM
Type
B38M
Broadcasting now · callsign TVS7KQ · 37,000 ft
Flights observed
1
Distinct callsigns
1
Country
CZ
Last broadcast
13h ago

Current position

49D423 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 49D423 falls within the block assigned to Czech Republic (CZ) by ICAO Annex 10, Volume III. Every aircraft registered in Czech Republic 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
TVS26M Smart Wings 1 2026-04-14

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-14 TVS26M PRG → ACE Apr 14, 10:15 UTCApr 14, 11:05 UTC50m

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 OK-SWM page for operator, model, and routing details .

Mode-S 49D423 frequently asked

What is Mode-S code 49D423?
49D423 is an ICAO 24-bit transponder address. Allocated to Czech Republic. Assigned to OK-SWM.
Where is Mode-S 49D423 registered?
Mode-S code 49D423 is allocated to Czech Republic (CZ). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 49D423 broadcasting right now?
Yes. Mode-S 49D423 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 49D423, octal 22352043, decimal 4,838,435.
What flights does 49D423 operate?
Mode-S 49D423 has broadcast 1 distinct callsign, including TVS26M.