sensors Mode-S transponder

34740B

ICAO 24-bit transponder address · allocated to Spain

Hex
34740B
Octal
15072013
Decimal
3,437,579
Country
ES
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
2
Country
ES
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 34740B.

Country allocation

The ICAO 24-bit address 34740B 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 2 distinct

Callsign Airline Flights Last seen
BOMB04 - 4 2026-06-18
LEYRE3 - 1 2026-06-12

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-18 BOMB04 - Jun 18, 14:55 UTCJun 18, 16:05 UTC1h 10m
2026-06-18 BOMB04 - Jun 18, 10:25 UTCJun 18, 11:35 UTC1h 10m
2026-06-17 BOMB04 - Jun 17, 17:30 UTCJun 17, 17:50 UTC20m
2026-06-17 BOMB04 - Jun 17, 15:10 UTCJun 17, 15:50 UTC40m
2026-06-12 LEYRE3 - Jun 12, 11:00 UTCJun 12, 11:20 UTC20m

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 34740B frequently asked

What is Mode-S code 34740B?
34740B is an ICAO 24-bit transponder address. Allocated to Spain.
Where is Mode-S 34740B registered?
Mode-S code 34740B is allocated to Spain (ES). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 34740B 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 34740B, octal 15072013, decimal 3,437,579.
What flights does 34740B operate?
Mode-S 34740B has broadcast 2 distinct callsigns, including BOMB04, LEYRE3.