ATLAS lab moves to certify hybrid over-moulded composite parts for e-VTOL aircraft

The Advanced Technologies Lab for Aerospace Systems (ATLAS) at Wichita State University's National Institute for Aviation Research (NIAR) is moving to certify parts made with its hybrid over-moulding process for thermoplastic composites. ATLAS demonstrated the process last year, showing it could produce complex composite structures in minutes. There is a problem: no standard test methods exist yet for certifying parts made this way, so ATLAS is now developing those methods from scratch.

The certification framework covers three areas: material compatibility, quality assurance protocols, and durability and damage tolerance testing. What's new here is that existing aerospace composite certification pathways don't cover this process, so ATLAS has to create the test methods itself before any manufacturer can put these parts on a flying aircraft.

The initial target application is electric vertical take-off and landing (e-VTOL) aircraft, and Joby Aviation and other companies collaborated with ATLAS on the underlying research. The proof point is a tail tip rib, one of the most complex structural parts on an e-VTOL airframe. ATLAS says the hybrid over-moulding process can produce that part in under two minutes. A metal version of the same rib typically takes up to 80 hours of CNC machining and removes 80 percent of the starting material as waste. The composite version comes out near net shape, with far less machining and material waste, and weighs 30 percent less than the metal part.

"People are not going to believe it's possible," said Waruna Seneviratne, ATLAS director and senior research scientist for composites and structures, during a presentation at the ACMA Thermoplastics Composites Conference in May. The project took first place in the SAMPE26 Outstanding Technical Paper Awards competition.

The work builds on an earlier ATLAS program that applied similar high-rate hybrid moulding techniques to aircraft window plugs. ATLAS is one of 13 NIAR research centers, with a stated mission of developing manufacturing methods for the "factory of the future" and training workers for advanced manufacturing careers. ATLAS hasn't set a timeline for finishing the certification framework, and until the material compatibility, QA, and damage tolerance test methods are validated, the hybrid over-moulding process remains a research demonstration rather than a qualified production process for flight hardware.