Why is ARINC 429 the Dominant Transmission Standard in Avionics?
Category : Arinc 429
Real time transmission of information is the key to avionics success, which enable pilots to make critical decisions about the aircraft while it’s on flight. Whether it is for military or commercial purposes, ARINC 429, one of the most widely used avionics standards in the world today and among the 300 or so standards published by Aeronautical Radio, Inc. (ARINC) since 1949, is capable of 32-bit data transmission at a speed of 100 kilobits per second, two different speed configurations, unidirectional flow of data, low cost implementation and design, all with a proven record of efficiency and integrity.
Still Relevant in the 21st Century
Even as the aviation industry hopes to leverage solar energy to power the modern aircraft in the first quarter of the 21st century, the avionics market is still huddled over the ARINC 429, which beats the slightly less popular and sincerely outdated Mil-Std-1553 data bus technology, thanks to the latter’s complex mechanism and the inability to address and tackle security risks. Sure the 1553 is not dead yet with ongoing efforts to reinvent the standard so that it can support aircraft data transmission with lower error rate and higher noise immunity. But, the comparison between the ARINC 429 and the 1553 or any of its successors like the 629 is not really relevant here as electronic system designers focus on simplistic modules which the contestant satisfactorily provides. Perhaps its biggest merit is the ability to transfer data at two different speeds. A low speed of about 14.5 kilobits per second for non-critical applications and a higher speed for applications that need the pilot’s immediate attention. Even if we consider its only weakness of not being able to correct the errors that it detects, decline of the ARINC standard hardly seems probable.
History is Kinder to the ARINC 429
Going back to the history of the data bus standards, during the boom of the aviation industry in the early 70s, ARINC developed a handful of transfer systems (with the most popular being the 419 specification) each of which were capable of a certain special characteristic. But, as the demands started to grow, especially from the commercial airline manufacturers, the necessity to integrate many of these characteristics into a single package came to the fore. Thus, in 1977, the organization published the ARINC 429, a hybrid “Digital Information Transfer System (DITS)” that exhibited a lot of desirable advantages such as high reliability, easy structure and installation, and most importantly, high efficiency. The last merit brought smiles to the aviation industry at large, making it the standard.
Decades-old Standard Still Going Strong
Since then, the 429 specification has braved the industry for decades without a single change in its basic design. Of course, many more standards were released, most notably the ARINC 664 Part 7 (commonly known as AFDX), which focused more on safety, but there’s no denying that the reliability and universal acceptance that it has enjoyed for close to forty years makes it all-powerful.
Today, modern aircraft like the Boeing 737 and the Airbus A320 make use of the ARINC 429 in their avionics which highlights the fact that necessity is after all the mother of invention.