PHOENIX—A 3D-printed engine part produced by Honeywell is reported to be the first FAA certified, flight-critical engine part produced using additive manufacturing.
The part, known as the #4/5 bearing housing, is said to solve critical supply chain challenges for complex aircraft engine parts. It is currently in production and was installed on an in-service engine, the company said in a release. The #4/5 bearing housing is a major structural component in the ATF3-6 turbofan engine used on the Dassault Falcon 20G maritime patrol aircraft, which are used by the French Navy for patrol and search-and-rescue missions, the release said.
Designed by Garrett in the 1960s and certified in 1967, the ATF3-6 engine is rare today, with only about a dozen ATF3-6 engines still flying. This presents sourcing and supply chain challenges for operators of Dassault Falcon 20G aircraft. The #4/5 bearing housing is a complicated part to manufacture, making it extremely costly for operators to replace due to the low quantity of orders placed. This challenge is combined with the high cost of tools needed to produce parts with traditional casting methods, where molten metal is poured into a mold and allowed to harden.
With additive manufacturing, these parts can be printed much more quickly and in smaller quantities without the need for expensive tools. During this process, components are built from the bottom up, with layers of powdered metal fused on top of one another using a laser.
“Though there aren’t many in service, Honeywell is responsible for supporting and maintaining these engines,” said Jon Hobgood, vice president of manufacturing engineering, Honeywell Aerospace, in the release. “We had to find a way to address these supply chain issues and keep these aircraft flying. We were able to use our expertise in additive manufacturing to produce the qualified part much faster, reducing our lead time from approximately two years to two weeks.”
Parts such as the #4/5 bearing housing are considered “safety-critical or flight-critical by regulatory bodies, meaning they must always function properly. Malfunction or failure of these parts would pose a major threat to passenger and crew safety and could cause significant damage to an aircraft. Safety-critical parts face increased scrutiny and must be approved by regulatory organizations like the Federal Aviation Administration (FAA) before they can be used on an aircraft. This makes the process from development to qualification a lengthy one, according to Honeywell.
Honeywell said in the release that it has been working closely with the FAA on the development and certification of multiple additive-manufactured components. These efforts have enabled the bearing housing to become what is reported to be the first component approved under the normal FAA delegated authority, further reducing the time for qualification.
“This is a major milestone for Honeywell because it demonstrates the maturity of our additive manufacturing operations and paves the way for us to print more certified, flight-critical parts in the future,” Hobgood said in the release. “It also is a major win for the additive industry, as flight-critical parts face heavy scrutiny and high standards for qualification and installation on aircraft, but this shows it can be done.”
Production is currently underway for the #4/5 bearing housing, with dozens more of the bearing housing expected to be produced by the end of 2020. Honeywell began its efforts in metal additive manufacturing in 2007 at its lab in Phoenix. The company said that it currently produces hundreds of different aircraft components with 3D printing.