sensors Mode-S transponder

A4A9AD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N4TW · CUB CRAFTERS CC-11 Carbon Cub · operated by WIENS TIMOTHY D

Hex
A4A9AD
Octal
51124655
Decimal
10,791,341
Country
US
Tail
N4TW
Type
CC11
No current signal · last broadcast 16d ago
Flights observed
2
Distinct callsigns
1
Country
US
Last broadcast
16d ago

Last known position

Most recent position reported by Mode-S A4A9AD.

Country allocation

The ICAO 24-bit address A4A9AD 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
N4TW - 2 2026-05-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-05-13 N4TW FNL → BJC May 13, 22:10 UTCMay 13, 22:40 UTC30m
2026-05-13 N4TW BJC → FNL May 13, 21:15 UTCMay 13, 21:45 UTC30m

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 N4TW page for operator, model, and routing details .

Mode-S A4A9AD frequently asked

What is Mode-S code A4A9AD?
A4A9AD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N4TW.
Where is Mode-S A4A9AD registered?
Mode-S code A4A9AD 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 A4A9AD broadcasting right now?
No active broadcast right now. Last signal was 16d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4A9AD, octal 51124655, decimal 10,791,341.
What flights does A4A9AD operate?
Mode-S A4A9AD has broadcast 1 distinct callsign, including N4TW.