Collier Aerospace enables Swift Engineering to optimize X-59 nose cone

Design and analysis software from Collier Aerospace Corp., developer of the HyperX computer-aided engineering (CAE) solution, was chosen by Swift Engineering Inc. for structural sizing, analysis, and test validation of the low-boom X-59 aircraft’s nose cone. This experimental aircraft from Lockheed Martin Skunk Works is part of the Quesst (Quiet Supersonic Technology) mission of U.S. National Aeronautics and Space Administration (NASA) to quiet loud sonic booms. Swift Engineering was contracted to build and perform structural analysis and certification testing for the X-59’s distinctive, 35ft-long nose cone, designed to control aerodynamic pressure waves (shock waves), that form at the sharp nose tip during supersonic flight, resulting in quieter sonic booms.

The software enabled Swift Engineering to remove mass, reducing the nose cone’s weight by more than 25% while maintaining dimensional stability and evaluate the design for a range of load cases; and provide detailed stress reporting to support part release and fabrication. The company also used the software to perform detailed analyses, supporting structural testing substantiation of the structural design.

“The Collier Aerospace software played a critical role throughout this high-visibility project to design, engineer, and build the X-59 nose structure,” said Bill Giannetti, technical consultant to Swift Engineering. “At the outset, when the team from Skunk Works explained how important lightweighting was, I had so much confidence in the software that I was convinced we would remove 100 lb from the nose cone. However, we surpassed that goal by achieving a significant weight savings of over 25% on the nose cone structure.”

Giannetti added, “We were able to iterate the structural sizing software with our finite element analysis solver, which enabled weight reduction through structural optimization and rapid load path convergence. Once the system was set up, we could literally watch the mass come out of the nose structure, while meeting all the traditional aerospace failure criteria simultaneously. It’s a fantastic software tool.”

To lower the weight of the approximately 400 lb preliminary design, which specified graphite/epoxy composite and a honeycomb-core sandwich structure, Swift Engineering’s team removed unnecessary plies, simultaneously optimizing the structure for stress and stability. The Collier Aerospace software enabled the team to quickly evaluate design alternatives by considering trade-offs in ply-layup schedules and core panel and edge band thicknesses, and then rapidly evaluate the change to the section stiffness and deflection.

The software enabled the company to deliver the nose cone ahead of schedule and under budget.

The goal of the X-59 aircraft, which is expected to make its first flight in 2025, is to help establish an acceptable noise standard for commercial supersonic flights over land, potentially resulting in U.S. and international regulators lifting a five-decade-long ban that was imposed due to loud sonic booms. Thanks to its unique geometry, particularly the elongated nose cone, the X-59 is expected to generate a barely audible thump rather than a boom, reducing noise impacts.

“We’re grateful that our software helped Swift Engineering achieve success with the X-59 nose cone and met the high expectations of Lockheed Martin Skunk Works,” commented James Ainsworth, vice president, Engineering Services, Collier Aerospace.