sensors Mode-S transponder

346491

ICAO 24-bit transponder address · allocated to Spain

Currently assigned to EC-NKF · TECNAM P-2006T

Hex
346491
Octal
15062221
Decimal
3,433,617
Country
ES
Tail
EC-NKF
Type
P06T
No current signal · last broadcast 2h ago
Flights observed
6
Distinct callsigns
6
Country
ES
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 346491.

Country allocation

The ICAO 24-bit address 346491 falls within the block assigned to Spain (ES) by ICAO Annex 10, Volume III. Every aircraft registered in Spain 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 6 distinct

Callsign Airline Flights Last seen
FBY99T - 1 2026-05-29
FBY99D - 1 2026-05-29
FBY53D - 1 2026-05-20
FBY53C - 1 2026-05-20
FBY53B - 1 2026-05-20
FBY53A - 1 2026-05-20

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-05-29 FBY99D - May 29, 14:40 UTCMay 29, 14:50 UTC10m
2026-05-29 FBY99T - May 29, 11:00 UTCMay 29, 11:20 UTC20m
2026-05-20 FBY53D - May 20, 15:00 UTCMay 20, 15:50 UTC50m
2026-05-20 FBY53C - May 20, 14:00 UTCMay 20, 14:20 UTC20m
2026-05-20 FBY53B - May 20, 10:45 UTCMay 20, 11:40 UTC55m
2026-05-20 FBY53A - May 20, 09:40 UTCMay 20, 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 EC-NKF page for operator, model, and routing details .

Mode-S 346491 frequently asked

What is Mode-S code 346491?
346491 is an ICAO 24-bit transponder address. Allocated to Spain. Assigned to EC-NKF.
Where is Mode-S 346491 registered?
Mode-S code 346491 is allocated to Spain (ES). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 346491 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 346491, octal 15062221, decimal 3,433,617.
What flights does 346491 operate?
Mode-S 346491 has broadcast 6 distinct callsigns, including FBY99T, FBY99D, FBY53D, FBY53C, FBY53B.