SAE Revamps Foundational Aviation Safety Standards for Changing Industry

SAE International is currently working on the release of revised versions of two longstanding critical modern aviation safety standards used for product assurance and certification of civil aircraft. These updates will affect aviation OEMs and suppliers across the board, realigning regulators and industry in a rapidly transforming industry.

The two standards—ARP4754, the development assurance process, or the ‘what to do book’, and ARP4761, the safety assessment process, or the ‘how to do it’ book—originally arose from the discussion and collaboration process in the SAE’s S-18 Aircraft and Systems Development and Safety Assessment committee, formed in 1992 based on a recommendation by the FAA. 

The two standards were originally released in late 1996. 

The committee is currently set to release the second revision of ARP4754, or revision B. “That is a more general update with improvements to correct potential interpretation issues that we had received feedback on,” said Eric Peterson, aerospace safety engineer with the FAA and the vice chair of the S-18 committee during that standard’s revision process. “We were trying to improve some of that.”

The committee hopes to get both revised standards released at the same time, or “as close to the same day as practical,” according to Mike Noorman, an aerospace consultant who has been on the committee for ten years and took over chairing the committee in April 2023.

Aligning on Safety as Industry Advances

The revised standards will address technical changes in aviation over the last 20 to 30 years. 

Back in the early 90s, during the digital age, Peterson recalled, things were getting very complicated very quickly in aviation technology. “It was becoming difficult to compare and ensure that each aircraft was satisfying the same safety objectives, because everybody was doing different techniques using different processes. The FAA came out and said, ‘Hey, we need to get the industry together and, here’s the best way to do that.’”

Noorman said that he thinks most of the revision activity has been about just trying to make sure that the industry is in alignment with what the regulators are looking for when it comes to aircraft system development processes and safety processes.

“One of the biggest needs for these updates was to really help people new to the industry that are maybe not as experienced when they’re reading them,” Noorman said. “Safety is not about just generating an analysis document. It’s not about just reviewing something. You’re an integral part of the development process.”

The Work of the S-18 Committee

Leading up to the revised releases, the committee has been assessing the behaviors designed into aircraft and systems, figuring out the risks and the criticality of those risks, and then coming up with a process to assure that those risks have been addressed and make sure that the vehicles are safe.

David Alexander, senior director of standards at SAE, said that his team facilitates the development of the standards by, in part, organizing and facilitating meetings, and providing the online workspace for the committees to write, discuss, and manage their standards. 

The committee wants to make sure they are producing documents which are scalable and usable for a number of different applications. “SAE has strong relationships with regulatory agencies like the FAA, NASA and their counterparts around the world who use industry documents like ARP4754 and ARP4761 as an accepted means of compliance to support the certification process,” Alexander said.

ARP4754 has always been about what you needed to do at the hardware and software level, according to Noorman. Revision A of ARP4754, published by SAE in December 21, 2010, got even more explicit in this regard, he said. “It identified the types of things that you need to do for developing a function, and then if your function is made up of hardware and software, this is how you might interface from a development assurance perspective.”

The committee wants ARP4754B and ARP4761A to align with each other, Noorman said. “We want you to be able to have both documents, with no question about what the interfaces between the system process and safety process are.”

The Challenges

One of the committee’s challenges was dealing with the sheer size of the documents—ARP4754 comes in at around 115 pages, and is intended to be used as a reference, while ARP4761 is 331 pages. The committee wants to couple the two documents together. “These two books are huge,” Peterson said. “That’s why it takes so long to create and get consensus.”

Another challenge is cybersecurity. Noorman said that the versions of the two documents about to be released don’t address cybersecurity in any way. “That was intentional. As a committee, what we like to do is, from a strategy perspective, look at what the emerging things are within industry, where there’s a team of people that say, ‘Hey, we think we need to write something on this but it may not have reached the point of industry consensus yet,’” he said.

They may be standing up their own working group to explicitly address cyber resilience and safety in the near future.

Revisions Today Working for Tomorrow

Standards like these two are an increasingly important part of the future because there’s a lot of real dynamism in the aviation industry right now, Alexander said. “Not just in terms of building or developing the next products to support more long-standing aircraft types of designs and operations, but also looking at some of the newer forms of aviation, whether that’s unmanned systems both commercial and defense, and use of things like supersonic passenger jets and other advanced mobility vehicles,” he said. “These standards have to be designed in a way that will support different applications and maintain the integrity and safety for which these vehicles and operations have to comply.”