sensors Mode-S transponder

AD9A33

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N976CT · DIAMOND DA-20 · operated by INVERTED HOLDINGS LLC

Hex
AD9A33
Octal
53315063
Decimal
11,377,203
Country
US
Tail
N976CT
Type
DV20
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AD9A33.

Country allocation

The ICAO 24-bit address AD9A33 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
N976CT - 4 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 N976CT - Apr 13, 22:10 UTCApr 13, 23:30 UTC1h 20m
2026-04-13 N976CT - Apr 13, 20:00 UTCApr 13, 20:10 UTC10m
2026-04-13 N976CT - Apr 13, 17:50 UTCApr 13, 18:45 UTC55m
2026-04-12 N976CT - Apr 12, 19:30 UTCApr 12, 20:15 UTC45m

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 N976CT page for operator, model, and routing details .

Mode-S AD9A33 frequently asked

What is Mode-S code AD9A33?
AD9A33 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N976CT.
Where is Mode-S AD9A33 registered?
Mode-S code AD9A33 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 AD9A33 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 AD9A33, octal 53315063, decimal 11,377,203.
What flights does AD9A33 operate?
Mode-S AD9A33 has broadcast 1 distinct callsign, including N976CT.