sensors Mode-S transponder

A4EA9D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N416CA · PIPER PA-28-140/150/160/180 · operated by COAST FLIGHT TRAINING AND MANAGEMENT INC

Hex
A4EA9D
Octal
51165235
Decimal
10,807,965
Country
US
Tail
N416CA
Type
P28A
Broadcasting now · callsign N416CA · 1,125 ft
Flights observed
6
Distinct callsigns
1
Country
US
Last broadcast
32m ago

Current position

A4EA9D is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A4EA9D 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
N416CA - 6 2026-04-24

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-24 N416CA - Apr 24, 20:00 UTCApr 24, 21:15 UTC1h 15m
2026-04-24 N416CA - Apr 24, 17:25 UTCApr 24, 18:30 UTC1h 5m
2026-04-23 N416CA RBD → RBD Apr 23, 23:05 UTCApr 24, 00:25 UTC1h 20m
2026-04-23 N416CA - Apr 23, 20:45 UTCApr 23, 22:20 UTC1h 35m
2026-04-23 N416CA - Apr 23, 17:35 UTCApr 23, 19:15 UTC1h 39m
2026-04-23 N416CA - Apr 23, 00:35 UTCApr 23, 02:15 UTC1h 40m

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 N416CA page for operator, model, and routing details .

Mode-S A4EA9D frequently asked

What is Mode-S code A4EA9D?
A4EA9D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N416CA.
Where is Mode-S A4EA9D registered?
Mode-S code A4EA9D 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 A4EA9D broadcasting right now?
Yes. Mode-S A4EA9D is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4EA9D, octal 51165235, decimal 10,807,965.
What flights does A4EA9D operate?
Mode-S A4EA9D has broadcast 1 distinct callsign, including N416CA.