sensors Mode-S transponder

A9DDCE

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N735BY · CESSNA 182 Skylane · operated by PILUSO MICHAEL S

Hex
A9DDCE
Octal
52356716
Decimal
11,132,366
Country
US
Tail
N735BY
Type
C182
No current signal · last broadcast 14h ago
Flights observed
3
Distinct callsigns
1
Country
US
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S A9DDCE.

Country allocation

The ICAO 24-bit address A9DDCE 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
N735BY - 3 2026-04-18

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-18 N735BY - Apr 18, 20:00 UTCApr 18, 20:30 UTC30m
2026-04-18 N735BY - Apr 18, 18:05 UTCApr 18, 18:30 UTC25m
2026-04-16 N735BY - Apr 16, 11:25 UTCApr 16, 12:00 UTC35m

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 N735BY page for operator, model, and routing details .

Mode-S A9DDCE frequently asked

What is Mode-S code A9DDCE?
A9DDCE is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N735BY.
Where is Mode-S A9DDCE registered?
Mode-S code A9DDCE 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 A9DDCE broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9DDCE, octal 52356716, decimal 11,132,366.
What flights does A9DDCE operate?
Mode-S A9DDCE has broadcast 1 distinct callsign, including N735BY.