The Basics of A429

Even though we spend takeoff clutching our seat handles, there is actually a lot more that goes into getting a plane into the air than a lot of fuel and a powerful engine. One of the most important aspects of safe and efficient air travel is successful communication, in which A429 plays a large role. Read on to learn more about some of the basics of this technology.

Important Words to Know
To fully understand this technology, it’s crucial to have at least a basic understanding of some of the components that make it work.

• Twisted pair – a type of wiring invented by Alexander Graham Bell in which two conductors of a single circuit are physically twisted together for the purpose of canceling out electromagnetic interference from external sources.
• Data words- in computing, a data word is a term for a unit of data used by a particular process design. It is a fixed-sized piece of data handled as a unit by the processor.
• Radar Altimeter – used on aircrafts to measure the altitude about the land beneath the plane by timing how long it takes a beam of radio waves to reflect back from the ground.

What Exactly is It?
A429 refers to Aeronautical Radio INC, the technical standard for the leading avionics data bus commonly used on higher-end transport and commercial aircraft. It refers to the defining physical and electrical interfaces of the two-wire data bus and data protocol required to support an aircraft’s local area network, or LAN.

How Does It Work?
The technology uses a self-clocking, self-synchronizing data bus protocol, with twisted physical wire pairs connecting to balance differential signaling. Data words are 32 bits in length, as most message consist of a single data word.

Where is It Used?
A429 is used in most avionics systems to meet environmental requirements. It uses several techniques to ensure that electromagnetic interference with on-board radios and other equipment does not hinder the safety or course of the flight. They are used in a number of different systems on board the plane, including flight management computes, inertial reference systems, radar altimeters, air data computer, radios, and GPS sensors.