Nadcap Certification Assures Design Quality for Aerospace Applications
Components developed for aerospace applications must meet a number of rigorous requirements to help ensure safety and reliability. Various industry accreditations and certifications are used to verify that components can meet these requirements.
The National Aerospace and Defense Contractors Accreditation Program, or Nadcap, is one such certification suppliers can achieve. Doing so signifies a company’s products meet the quality, innovation and performance standards of aerospace and defense applications.
Power & Motion: Are you able to give an example of the specifications or standards that you need to meet for the certification?
Steve James: There is a processing standard that the SAE organization wrote called AS6414 for processing of elastomers for aerospace. It outlines all these requirements that we need for production of elastomers for the aerospace community. With that, the Nadcap committee has created a check sheet, AC7115, the auditor goes down and asks questions that are based upon that standard. Both Bruce and I participate in creating the standards and creating the audit questions and reviewing them to make sure they're accurate. But again, the auditor came into CDI and asked those questions, and we've successfully passed the requirements.
This is used across the board, throughout the aerospace market, both the commercial and defense [sectors]; you can include space and ground support too. It's a recognized, call it a small club, that has the Nadcap accreditation and meets these requirements. Not every elastomer producer has it.
Power & Motion: What goes into achieving certifications such as Nadcap?
Steve James: We had to form a good cross functional team. Internally, we had our chemist Bruce, we had process engineering, quality, R&D, our lab personnel, and lab managers all get together. [Given it was an] external audit, we had a guidance person that the Nadcap committee assigned to us, and they helped us through the process.
So, Bruce had to design the elastomers. We had to have our laboratory people test those and get the third-party accredited testing done to them, and then we had to produce them out in the shop…we had to [supervise] and look at procedures, policies and training records to make sure they all met the processing standard requirements.
Bruce Fu: One thing I want to add is we did a lot of training for everyone involved, pretty much every team — materials, engineering, manufacturing. In the end, I think it’s totally worth the time. It gives us the confidence that we can deliver high-quality products.
Steve James: Bruce even met with our supply chain and quality people to do an audit of the vendors that supply us ingredients that go into the compounds that we design. We really touched every department within CDI.
Kyle Ward: From the engineering perspective, [we] helped the manufacturing and production teams finalize their procedures, making sure everything aligns cross functionally. When we approach our customers [and] provide solutions for their applications, we have that accreditation showing that we can provide not only the design, but also the materials and the quality standards that go with it to meet their internal specifications and industry specifications.
Power & Motion: Can you expand on how achieving certifications like Nadcap play into product development efforts?
Kyle Ward: With Nadcap, each elastomer has to meet a specific test and requirement. Those can be characterized into different application criteria — pressure, temperature, and media compatibility — for each part of the airplane or ground service [vehicle] that these elastomers are used in. For the engineer, we use that data and supply it to the customers, proving that our compounds do meet their fluid compatibility and temperature requirements, such as those that are very cold towards the flight control sections, and then also very hot towards the engine section.
And then we also design using our internal design knowledge to provide a solution. We work with a customer, because sometimes we don't always know everything, so we work as a team with them to make sure we are also providing the best solution possible, and we're on the same page. And that Nadcap certification just gives us a little extra confidence with them versus another supplier.
A lot of customers, especially if we are new partners, have an audit team that comes in and audits our process. Now they will still do that, but the Nadcap certification gives the extra layer of protection showing that a third party has already come in and done that audit. So, it’s a little bit less intensive, and they tend to trust you more. It'll be more of a partnership, rather than an inspection, because that's already been done.
Power & Motion: To switch gears a little with our discussion, what are some of the key design requirements for those products you are developing, such as seals and wear components, for use in aerospace applications?
Steve James: If we’re looking at an engine application, we've got requirements [related to them] trying to take some weight out to make the engines more efficient. We have new fuels — there's discussions about biofuels out there…and hydrogen — so that plays into our product development and how we see the future of aerospace going.
Other aspects of the planes we look at, like Kyle was saying, are the fluid compatibility and the temperature ranges which are used on the aircraft. That allow us to either adjust one of our standard designs, or create a new product to help the customer fulfill their requirements. At the same time, the newer technologies, fluids and lower temperatures that the aerospace industry is seeing allows us [and] our elastomer and thermoplastic chemists to be on the leading edge to develop these materials and products that will help solve tomorrow's solutions.
Kyle Ward: We have to make sure that with the new fluids [and other developments] that our elastomers are proven to those new technologies as well as the legacy ones.
Bruce Fu: When it comes to materials, both us and our customers are especially focused on long-term reliability in extreme conditions. We're developing quite a few materials that can handle a very wide temperature range and resist a broad spectrum of chemicals — some are very aggressive, including those sustainable fuels — and also prevent corrosion.
On top of that, the material still has to meet all the usual performance requirements, such as physical properties, wear resistance, and protection against weather. So, there's really no one size fits all solution.
Power & Motion: Are there any specific types of features or design attributes customers in the aerospace marketplace are looking for from their seal and wear products?
Steve James: They’re looking for a long service life, whether that be measured in the FAA (Federal Aviation Administration) or EASA (European Union Aviation Safety Agency) checks on the airplane to see if they can push that farther, or the performance of the actual seals in functional parts to give them an advantage over their competition. In supplying the aerospace industry, things like friction, leakage and life — being able to go longer, say instead of lasting 5 or 6 years we’re seeing 14-18 years and some customers looking at 20 years’ worth of product lifespan. They're [aerospace customers] trying to push performance levels up to be at the leading edge of producing an actuator or an engine that could [last] longer. So that's mainly what we see besides, again, the new fluids and types of greases that we have to be compatible with.
A lot of the design things that we deal with on day-to-day basis are low friction and longer seal life; if it were one of our thermoplastic parts, like our PTFE (polytetrafluoroethylene) seals, we’d be talking about the wear [properties]. On the elastomers, it’s different properties like compression set or abrasion. So, we're looking at those properties to be able to give our customers a longer seal life.
Kyle Ward: From the design aspect, using our Arylast portfolio of elastomers for aerospace, we have to look at not only the wear life and the compatibility with the fluids internally, but we also have to look at how UV effects them and also the cleaning [products] that they use on the airplanes. We don't want those cleaning [products] to affect our seals or wear components. So, we have to make sure that those are properly suited, which decreases [how often] they are changing out components, so it keeps them in the air longer. That's our entire goal.
Power & Motion: What are some of the design challenges you face when developing seal and wear products for aerospace applications? Are these challenges unique to this market or are they similar to those experienced when developing products for other markets as well?
Steve James: One of the things is that sometimes our customers don't know all the operating conditions; they're also learning as they're trying to develop [products]. It's purely research and development on their end too. When Kyle or any of the other engineers are talking to customers, they're trying to pull [from them] what are the conditions that the seal or wear components have to perform in. The customer may or may not know the complete answer. Very seldom on a research and development project do they know every operating condition; there's some assumptions and guesses. We have to go through and work together with the customer to provide them a great sealing solution but at the same time have the flexibility when something's not working during evaluation to be able to work with the customers to switch out [a product] and react very quickly.
That’s not really unique to the aerospace industry, some other industries may have the same challenges. But what makes the aerospace industry, I think, unique is that aerospace, space and defense are always the leaders of technology in pushing the envelope of products and materials, in seeing where they need to be improved [and if there] is a gap in the material portfolio throughout the industries. A lot of innovation has come throughout the years from the aerospace industry.
Power & Motion: What are some of the trends or design needs CDI sees for aerospace applications and how, if at all, are these influencing the company’s product development?
Steve James: The evolving needs of our aerospace customers, and customers in general, are pushing CDI to innovate across materials [with] new designs and new manufacturing processes. They're pushing us to get better and more effective designs and be more efficient, whether it's to be able to get a lighter, more efficient aircraft, supporting electrification or using a long-term, reliable solution in a harsh environment.
CDI’s product development efforts are closely aligned with the industry trends and we're focusing on the future solutions as well as supporting and enhancing today's platforms. These trends not only drive engineering decisions, but also reinforces CDI’s role as being a trusted, forward-thinking partner within the supply chain for aerospace. There are a lot of things going on in airspace that are exciting; we've got the electric vertical take-off and landing (eVTOL) equipment, hydrogen fuels are being discussed, and electric aircraft.
