Hexcel core supports Boeing’s development of the MQ-25 Stingray

In a collaborative effort, Hexcel (Stamford, Conn., U.S.) has partnered with Boeing (Arlington, Va., U.S.) to test a critical component for the U.S. Navy’s MQ-25 Stingray unmanned aerial refueling aircraft. Hexcel’s recently launched Flex-Core HRH-302 honeycomb core material is being evaluated for use in the structure surrounding the high-temperature exhaust nozzle on the engine powering the MQ-25.

The MQ-25 Stingray is designed to provide much-needed aerial refueling capabilities to extend the range of carrier-based fighter jets like the F/A-18 Super Hornet, EA-18G Growler and F-35C. When this aircraft becomes operational, it will significantly enhance the combat radius of the U.S. Navy’s carrier air wing, according to the U.S. Navy.

The benefits of incorporating composite materials into the design of any aircraft, particularly in a UAV like the MQ-25, are considerable, according to Bobby Rowe, VP, product management, core and engineered products at Hexcel.

“In the case of the MQ-25, composite materials could allow for extended range and endurance, as well as increased payload capacity,” says Rowe. “Lighter UAVs can carry more fuel, which is particularly important in the vast expanse of the Pacific, where distances between operational areas and carriers can be significant. By reducing the weight of the UAV itself, more capacity could also be available for mission-specific payloads, such as sensors and other communications equipment.”

Understanding these operational benefits is core to the work of Hexcel’s product management team, adds Rowe. “When we develop composite materials for our military customers, we always keep the end in mind. If products like our honeycomb core can provide our customers an operational advantage, we know it will ultimately protect the men and women who go into harm’s way.”

Over the past year, product managers and manufacturing and operations teams from the Hexcel Casa Grande, Arizona, and Pottsville, Pennsylvania, facilities have been collaborating closely with Boeing engineers to develop a honeycomb product that could provide weight savings, cost savings, and reduced manufacturing and delivery lead times compared to other materials, without sacrificing the performance requirements for the aircraft.

“The flexibility and thermal performance of HRH-302 make it ideally suited for the complex curvatures and increasing heat loads found in next-generation aircraft nacelles, and as we continue our testing on this product, we believe it can help our customers achieve their goals of improving the performance and affordability of the MQ-25 system,” says Rowe.

The HRH-302 honeycomb core material is currently under evaluation for Boeing’s stringent design and mission performance imperatives, according to Clark Miller, a senior manager of Boeing Programs for Hexcel.

“One of the things that has been so gratifying about our collaboration with Boeing has been the ability to prototype a solution in near real time,” notes Miller. “We were able to quickly respond to their needs and provide a lightweight, high-temperature solution for the exhaust nozzle.”

Miller adds that Hexcel’s vertical integration and expertise in advanced composite materials is a key differentiator for the company. “By producing the honeycomb core at the Casa Grande facility and then shipping it to Pottsville for machining we streamlined the supply chain and enabled rapid prototyping and production for this new honeycomb material offering for our customer.”

Flex-Core HRH-302 is designed to sustain service temperatures up to 450°F, bridging the gap between traditional phenolic-based materials and high-cost polyamide solutions. Leveraging the expertise Hexcel has in thermoplastic resins, the product is said to offer improved thermal capabilities while maintaining similar mechanical properties to existing honeycomb materials.

“HRH-302 represents our commitment to staying a generation ahead and delivering products that meet the demands of our customers,” says Rowe. “We’re excited to work closely with our customers to demonstrate the benefits of this new material on critical military and commercial programs.”