RICHMOND, Virginia –
Creating items in three dimensions instead of two is sometimes compared to creating a sculpture instead of a portrait. Even though we live in a 3D world, engineers were limited for many years to 2D drawings/sketches to communicate thoughts and ideas. Today with technological advances in additive manufacturing methods and other technologies, engineers can go directly from a 3D idea to a 3D object.
In the early 1990s, Defense Logistics Agency witnessed the decline of once robust domestic supply chains and recognized the need to invest in future manufacturing technology.
Today, the agency continues to collaborate with the military services’ engineers, civilian industries and educational institutions to pursue advances in additive manufacturing practices.
DLA Aviation Commander Air Force Brig. Gen. Allan Day spoke with Defense Manufacturing Conference attendees in late 2016 in Phoenix, Arizona. The conference focused on additive manufacturing for hard-to-source and obsolete parts. The conference brought attendees together to exchange ideas, initiatives, and developments in manufacturing.
Day highlighted how DLA Aviation is moving from managing material to managing data and implementing a pathway to additive manufacturing.
Day said we are in the repair and flight worthy stage of using AM. He highlighted challenges in obtaining airworthiness certification and having robust processes that are repeatable as part of the agency’s goal to achieve process excellence. Dave Carns, director of DLA Aviation Engineering also attended the conference along with Kyle Hedrick, DLA Aviation’s additive manufacturing lead.
Day spoke about managing data/cyber security and developing universal standards as the industrial base transforms, stressing that, “We need to leverage our strengths to achieve common goals.”
Liz McMichael, Naval Air Systems Command’s Additive Manufacturing/Digital Thread Integrated Product Team lead, attended and participated in panel discussions. She briefed attendees on current NAVAIR AM projects. She stressed NAVAIR’s goal to help develop broad industry supported AM standards for military products. Industry AM standards, not just military standards, will enable suppliers to reduce investments in proprietary approaches and use proven and repeatable methods.
McMichael said NAVAIR is still educating customers on what AM is and the issues and risks in using it without engineering oversight.
“Legacy parts are a challenge,” said Hedrick. “We are running weapon systems way past their design life that have failing parts that weren’t intended to be replaced.” Hedrick started working for DLA Aviation two years ago, after having worked in engineering, product and business development in private industry for 25 years.
Legacy aircraft parts typically have 2D drawings or technical packages with part specifications. He said, “Industry is designing in 3D environments, and going forward DLA has to be able to support customer requirements using the best manufacturing processes available.”
Subtractive, or traditional, manufacturing is carving a part out of metal or material that has already been produced into the shape you want and then taking away material that you don’t want.
3D printing, also known as additive manufacturing, covers a variety of processes used to produce a three-dimensional object. In 3D printing, layers of material are laid down under precise computer control, building the 3D object one layer at time. These objects can be of almost any shape and are produced from 3D models with other supporting data sources.
Parts created by using AM techniques can be printed on demand with shorter lead times. With digital production and after an initial capital equipment investment, a supplier can create short, customized production runs with minimal set-up costs, according to McMichael.
When DLA Aviation isn’t able to find sources to provided legacy parts to meet customer needs, it turns to engineers and designers within the military engineering service activities and industry to recreate or reverse engineer the part using computer-aided design software and/or 3D scanners to create a 3D model, said Hedrick.
Sometimes, it seems that we, the Department of Defense, are slow to embrace technology, Hedrick said and added, caution is warranted as warfighters’ lives depend on the aircraft spare parts and structural items DLA provides, many of which have critical applications or are critical to flight safety.
McMichael is encouraged by Hedrick’s caution, adding there is a need to use mature AM processes and materials when creating parts.
She said AM may not necessarily be less expensive than traditional manufacturing processes. “The balance we need to strike is between cost versus shorter, production lead-times as we strive to increase readiness,” McMichael said.
McMichael said NAVAIR and DLA have had a memorandum of agreement since September 2015 after many discussions about what the “head hurter” parts are – those parts that are hard-to-source for various reasons.
NAVAIR engineers originally thought AM production of a safety critical part would take three years, but it’s moving much faster than they thought was possible. Flight testing of one of the first set of six safety critical 3D printed parts will begin this spring, 18 months earlier than planned.
DLA Aviation acquisition specialists and engineers; NAVAIR engineers; Fleet Support teams at Cherry Point, North Carolina and Patuxent River, Maryland; designers at the Naval Air Warfare Center Aircraft Division, Lakehurst, New Jersey; and partners from Pennsylvania State University’s Center for Innovative Materials Processing through Direct Digital Deposition form the core of the team.
DLA and NAVAIR are working together as NAVAIR works through the AM process for flight testing this spring. The first flight will test a titanium engine attachment fitting for the V-22, Osprey. Together, the agencies are developing the technical data packages to get flight critical parts into the supply chain and ensure there is a supplier base that is qualified and ready to make AM parts. NAVAIR intends to make and test five more items by the end of 2016.
“AM has requirements in terms of how you need to build components and test them that are fundamentally different than standard manufacturing,” said McMichael.
She went on to say that NAVAIR tests and inspects all 3D printed items to ensure they are safe for flight. AM specific testing is required for every production lot to ensure quality in the manufacturing process. This testing includes a process where additional items of material are built at the same time as the actual AM parts. These “coupons” of material are tested for each build and all AM production components are validated before they can be used on aircraft.
Once developed and validated, the AM technical data packages for AM created parts will be specific to the AM machine and material used. They include all of the details of materials, AM process parameters, coupons, and testing required - ensuring the AM parts can be produced consistently and used safely.
Hedrick noted that during last year’s conference DLA Aviation attendees gained insight into what challenges vendors in private industry are facing – the same challenges as DLA Aviation – how to supply legacy parts.
Hedrick said vendors using additive manufacturing processes are typically mid-to-large corporations with capital to invest who can handle the associated sunken costs, costs that can range from $500,000 to $2 million just for the machine that is capable of producing metal parts.
While expensive, Hedrick did say the machine costs are dropping and machines are versatile and can be used for manufacturing almost any kind of shape.
“We were able to see who wants to step forward and work with DLA,” said Hedrick. “If support providers can tackle this issue, then they are a leading company in the marketplace, a leader in this technology that we want to be doing business with.”