sensors Mode-S transponder

ADA5D1

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N979HP · AEROSPATIALE AS-350 Ecureuil · operated by CALIFORNIA HIGHWAY PATROL OFFICE OF AIR OPERATIONS

Hex
ADA5D1
Octal
53322721
Decimal
11,380,177
Country
US
Tail
N979HP
Type
AS50
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 ADA5D1.

Country allocation

The ICAO 24-bit address ADA5D1 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
CHP58 - 2 2026-04-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-13 CHP58 - Apr 13, 23:30 UTCApr 13, 23:40 UTC10m
2026-04-13 CHP58 - Apr 13, 16:40 UTCApr 13, 18:15 UTC1h 35m

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 N979HP page for operator, model, and routing details .

Mode-S ADA5D1 frequently asked

What is Mode-S code ADA5D1?
ADA5D1 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N979HP.
Where is Mode-S ADA5D1 registered?
Mode-S code ADA5D1 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 ADA5D1 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 ADA5D1, octal 53322721, decimal 11,380,177.
What flights does ADA5D1 operate?
Mode-S ADA5D1 has broadcast 1 distinct callsign, including CHP58.