sensors Mode-S transponder

A35C21

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N31526 · BEECH 36 Bonanza · operated by TROSTEL MANFRED E

Hex
A35C21
Octal
50656041
Decimal
10,705,953
Country
US
Tail
N31526
Type
BE36
No current signal · last broadcast 4h ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S A35C21.

Country allocation

The ICAO 24-bit address A35C21 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States 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
N31526 - 1 2026-04-20

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-20 N31526 TPA → SRQ Apr 20, 17:10 UTCApr 20, 17:35 UTC25m

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 N31526 page for operator, model, and routing details .

Mode-S A35C21 frequently asked

What is Mode-S code A35C21?
A35C21 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N31526.
Where is Mode-S A35C21 registered?
Mode-S code A35C21 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A35C21 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A35C21, octal 50656041, decimal 10,705,953.
What flights does A35C21 operate?
Mode-S A35C21 has broadcast 1 distinct callsign, including N31526.