What is ARINC 429?

ARINC (Aeronautical Radio Inc.) was founded in 1929 and operates under the Airlines Electronic Engineering Committee, responsible for setting standards within the aviation industry. These standards cover various aspects, such as the design, functionality, assembly, and communication protocols of aviation electronic equipment, and are commonly used in both civil and military aircraft systems. Among these, ARINC 429 stands out as a widely adopted serial data bus standard, facilitating communication between electronic devices in an aircraft.

ARINC-429 Specification

The ARINC-429 technical specification, initially known as the Digital Information Transfer System (DTIS), was introduced in 1977 to standardize communication between avionics systems and components in commercial aircraft. Now referred to as the Mark 33 Digital Information Transfer System, it remains the most widely used standard among airlines. This specification outlines the communication protocols for 429 bus systems, including word structures, electrical characteristics, and other requirements.

What sets ARINC 429 data transfer apart is its unidirectional data flow. While most data buses enable bidirectional communication across multiple points using the same set of wires, ARINC 429 only allows data to flow in one direction. However, this design is not viewed as a drawback by airlines, as it has led to enhanced system reliability and reduced long-term operational costs.