sensors Mode-S transponder

3571CD

ICAO 24-bit transponder address · allocated to Spain

Currently assigned to E.27-13 · PILATUS PC-21

Hex
3571CD
Octal
15270715
Decimal
3,502,541
Country
ES
Tail
E.27-13
Type
PC21
No current signal · last broadcast 3d ago
Flights observed
8
Distinct callsigns
6
Country
ES
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S 3571CD.

Country allocation

The ICAO 24-bit address 3571CD 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
TRD19 - 2 2026-04-14
TRD15 - 2 2026-04-15
TRD62 - 1 2026-04-15
TRD61 - 1 2026-04-14
TRD36 - 1 2026-04-14
TRD35 - 1 2026-04-15

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-15 TRD62 - Apr 15, 11:15 UTCApr 15, 12:20 UTC1h 5m
2026-04-15 TRD35 - Apr 15, 09:00 UTCApr 15, 10:05 UTC1h 5m
2026-04-15 TRD15 - Apr 15, 07:01 UTCApr 15, 07:50 UTC50m
2026-04-15 TRD15 - Apr 15, 06:40 UTCApr 15, 06:55 UTC15m
2026-04-14 TRD61 - Apr 14, 11:05 UTCApr 14, 12:10 UTC1h 5m
2026-04-14 TRD36 - Apr 14, 09:10 UTCApr 14, 10:05 UTC55m
2026-04-14 TRD19 - Apr 14, 07:10 UTCApr 14, 07:55 UTC45m
2026-04-14 TRD19 - Apr 14, 06:50 UTCApr 14, 07:10 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.

Prefer a tail-number view? See the E.27-13 page for operator, model, and routing details .

Mode-S 3571CD frequently asked

What is Mode-S code 3571CD?
3571CD is an ICAO 24-bit transponder address. Allocated to Spain. Assigned to E.27-13.
Where is Mode-S 3571CD registered?
Mode-S code 3571CD is allocated to Spain (ES). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3571CD broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3571CD, octal 15270715, decimal 3,502,541.
What flights does 3571CD operate?
Mode-S 3571CD has broadcast 6 distinct callsigns, including TRD19, TRD15, TRD62, TRD61, TRD36.