Avionics News February 2016 - 38
MOVING METHODS OF COMPLIANCE
Continued from page 37
Peri. Under its FAA charter, ASTM not only created the consensus AMOC standards, it also defined the LSA safety standards.
Part 23 safety standards are deemed governmental, Peri
noted, and the FAA cannot delegate them, as it did with LSA.
With the rewritten rule, Part 23 will still set the safety standards, and it will identify the source of the applicable consensus standard that complies with the requirement. Because the
rule setting the standard does not include the prescribed method of compliance, the consensus organization can update the
accepted method as technology dictates, providing the most
efficient, current and economical methods of complying with
the safety requirements.
Removing AMOCs from the rules also reduces their "sovereignty," Peri said. "When safety standards are at an appropriately high level, it is easier to harmonize them because the
AMOC in the consensus standard is not related to any one
nation's system." Developing the standard in the international
public domain allows the best minds involved in the subject to
unite with a common goal.
Another significant benefit of consensus standards is that
they allow those pursuing certification to use the standard that
best meets their needs without defining those needs. Peri explained this with an analogy: "The safety standard is a destination, like Frankfort, Germany. There are many different ways
to get there. You can go direct and nonstop for $2,000, or you
can change planes in Toronto for half the price or less."
Shops pursuing certification will need to update their technical libraries, Peri noted. "Consensus standards sourced by
the regulations are available online as read-only documents.
You can't print them, but you can see if the standard is applicable to what you're doing." If the standard applies to the
project, the shop can buy it, but it may be more economical to
join the organization because members get access to a whole
section of standards.
Perhaps without realizing it, aviation has relied on consensus
standards since its earliest days. In 1916, the American Society
of Aeronautical Engineers, whose members included Orville
Wright, Glenn Curtiss and Glenn Martin, asked the Society of
Automobile Engineers for oversight of technical standards for
their industry. Out of that meeting came a new organization,
and Elmer Sperry created the word "automotive," from the
Greek autos (self) and Latin motivus (of motion), to represent
any form of self-powered vehicle. Today, nearly 30,000 SAE
standards are employed in nearly every facet of aerospace, from
tools and materials to specific aircraft components.
Since 1941, all of the aviation hardware standards, which
now include hoses, electrical connections and terminations,
and similar components, have been managed and developed
by the Aerospace Industries Association. According to the
AIA, it has converted more than 500 military specifications
to national aerospace standards.
For more than a century, ASTM International has developed and maintained the consensus standards for thousands
of items, including aviation fuel, oil and other components,
such as light-sport aircraft. It also is the source of several
aviation guides, including Standard Practice for Design,
Alternation, and Certification of Airplane Electrical Wiring
There are two sources of standards for avionics. The Radio Technical Commission for Aeronautics was founded in
1935 as a private, nonprofit corporation that advised the government. Better known as RTCA, it "employs a consensusdriven process to generate minimum performance standards
for communication, navigation, surveillance, and air traffic
management equipment and systems; to forge recommendations on key aviation policies, and identifying and developing mitigation on issues that affect air traffic management
Founded in 1929, Aeronautical Radio Inc. was the airline
industry's single licensee and coordinator of radio communication. More commonly known as ARINC, it developed many
of the standards for the trays and boxes for line-replaceable
avionics. Today, ARINC standards number more than 500.
"With experimental, amateur-built aircraft representing a
quarter of the fleet of piston singles, I would hope that shops
working on their avionics would be familiar with using
ASTM standards because of LSA," Peri said. And some may
have been using them for years without fully realizing it.
Electrical wiring is the classic example. For the past decade,
shops have had the choice of AC 43-13 or the ASTM wiring
guidelines. They can also use an SAE standard that the FAA
has accepted as a method of compliance.
In the end, Peri said shops have little to be anxious about.
In its final report, the aviation rulemaking committee created for the Part 23 rewrite recommended a comprehensive
reorganization of the design requirements and "changes to
production, alterations, and continued airworthiness regulations, orders, and policies to support (the ARC's) goal of
twice the safety at half the cost."
And taking the long view, this advisory committee "wrote
them at a high enough level to address the full range of Part
23 products and will remain applicable for foreseeable and
unforeseeable technologies during the next 20 years." q