Read about Arinc 429 key features, usage and interference protection.

Click for ARINC-429 Avionics Cards  or ARINC-429 Analyzers

 

Aeronautical Radio INC (ARINC) is a global organization made up of airplane manufacturers and major airlines. It objective is the promotion of aircraft equipment standardization within the industry. The protocol assembled by ARINC not only defines the electrical characteristics and physical layer but also the format of the data sent over the bus. The ARINC 429 is today the most widely used data bus for transport and commercial aircraft. 

The data bus specification defines the way avionics systems and equipment ought to communicate with each other. These have been interconnected using wires in twisted pairs. The messages get transmitted at either a bit rate of 100 kilobits or 12.5 per second to other elements of the system monitoring the messages coming through the bus. The transmission and reception is done through separate ports making it necessary to have lots of wires on an aircraft, which typically use avionics systems in large numbers.

Key Features

The ARINC 429 driver may be employed in connecting OPAL-RT simulators to the ARINC 429 avionics data bus. Maximizing on all the advantages brought by HIL simulation (e.g., reduced process time, safety issues, and cost effectiveness), the usage of the arinc-429 interface in the HIL context substantially expedites the process of simulating, testing, debugging, and the operational avionics data buses applications. 

  • Easy configuration scheduling as well as manipulating messages in real-time
  • Support messages encoding and decoding
  • Advanced debugging features


At the receiver end, the protocol facilitates self-clocking, thus doing away with the need to have clocking data transmitted. It is based on PCI-400-2 or PCI-400 high-quality Max Technology carrier board together with IPM-429 IO module. This provides 32 or 64 channels that are divided into either 2 or 4 modules.

The Usage

This system has been installed on the majority of commercial transport aircraft. This includes the Boeing series 727, 737, 747, 757, and 767; Airbus A330/A340 and A310/A320; Bell Helicopters; and the McDonnell Douglas MD-11. The unidirectional system offers high reliability at the expense of limited data rates and wire weight. 

It has the capacity to transmit messages at 100 or 12.5 kilobits per second. Typically, in terms of length, the messages are one (data) word. The arrangement of the bit sequence is usually from the last to the first bit. In terms of label fields, the sequence then gets rearranged into an order that starts with the most significant bit coming first.

Interference Protection

The system employs a number of electrical, physical, and protocol techniques for minimizing electromagnetic interference coming from on-board radios as well as other types of equipment such as other transmission cables.

Bottom Line

The current ARINC specification documents can be acquired at a fee from Aeronautical Radio INC. They provide an overview of the ARINC protocols. Aeronautical Radio INC (ARINC-429) is also known as Mark 33 Digital Information Transfer System (DITS).