sensors Mode-S transponder

ACAD1D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N916BQ · CESSNA 172 Skyhawk · operated by 9K AIR LLC

Hex
ACAD1D
Octal
53126435
Decimal
11,316,509
Country
US
Tail
N916BQ
Type
C172
No current signal · last broadcast 1d ago
Flights observed
2
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S ACAD1D.

Country allocation

The ICAO 24-bit address ACAD1D 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
N916BQ - 2 2026-04-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-13 N916BQ - Apr 13, 20:30 UTCApr 13, 23:40 UTC3h 10m
2026-04-13 N916BQ - Apr 13, 15:55 UTCApr 13, 16:15 UTC20m

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 N916BQ page for operator, model, and routing details .

Mode-S ACAD1D frequently asked

What is Mode-S code ACAD1D?
ACAD1D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N916BQ.
Where is Mode-S ACAD1D registered?
Mode-S code ACAD1D 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 ACAD1D 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 ACAD1D, octal 53126435, decimal 11,316,509.
What flights does ACAD1D operate?
Mode-S ACAD1D has broadcast 1 distinct callsign, including N916BQ.