sensors Mode-S transponder

4C1E73

ICAO 24-bit transponder address · allocated to Serbia

Currently assigned to YU-HTT

Hex
4C1E73
Octal
23017163
Decimal
4,988,531
Country
RS
Tail
YU-HTT
Type
EC30
No current signal
Flights observed
0
Distinct callsigns
1
Country
RS
Last broadcast
-

Country allocation

The ICAO 24-bit address 4C1E73 falls within the block assigned to Serbia (RS) by ICAO Annex 10, Volume III. Every aircraft registered in Serbia 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
YUHTT - 60 2026-07-12

Recent flights

No flights recorded yet for this transponder.

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 YU-HTT page for operator, model, and routing details .

Mode-S 4C1E73 frequently asked

What is Mode-S code 4C1E73?
4C1E73 is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-HTT.
Where is Mode-S 4C1E73 registered?
Mode-S code 4C1E73 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C1E73 broadcasting right now?
No active broadcast right now.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4C1E73, octal 23017163, decimal 4,988,531.
What flights does 4C1E73 operate?
Mode-S 4C1E73 has broadcast 1 distinct callsign, including YUHTT.