sensors Mode-S transponder

A1ECD8

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N223HC · CESSNA 206 Stationair · operated by G206 LLC

Hex
A1ECD8
Octal
50366330
Decimal
10,611,928
Country
US
Tail
N223HC
Type
C206
No current signal · last broadcast 1d ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A1ECD8.

Country allocation

The ICAO 24-bit address A1ECD8 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
N223HC - 1 2026-04-20

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-20 N223HC SJU → SIG Apr 20, 13:45 UTCApr 20, 14:40 UTC55m

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 N223HC page for operator, model, and routing details .

Mode-S A1ECD8 frequently asked

What is Mode-S code A1ECD8?
A1ECD8 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N223HC.
Where is Mode-S A1ECD8 registered?
Mode-S code A1ECD8 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 A1ECD8 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1ECD8, octal 50366330, decimal 10,611,928.
What flights does A1ECD8 operate?
Mode-S A1ECD8 has broadcast 1 distinct callsign, including N223HC.