Maintainers from Marine Aircraft Logistics Squadron 36 and the 18th Maintenance Group collaborated to 3D-print a replacement cockpit cooling duct for a U.S. Air Force F-15 Eagle at Kadena Air Base in Okinawa, Japan, returning the aircraft to service in hours rather than the projected three to four months.
The Naval Air Systems Command Additive Manufacturing team, headquartered at Naval Air Station Patuxent River, provides training, engineering support, and technical data packages to Navy and Marine Corps units for producing parts in forward-deployed areas where supply chains face challenges.
Additive manufacturing builds objects layer by layer from digital designs, allowing on-demand production of components. U.S. Air Force Capt. Diego Carrillo, a depot liaison engineer, noted its value for non-procurable or long-lead-time items: “In applications where 3D manufactured parts are a viable option and are non-procurable or have a long lead time, using this capability can offer cost and time savings. This capability is critical when items are not available from the supply chain or cannot be purchased from industry when needed.”
Air Force maintainers discovered a crack in the right-hand cockpit cooling duct during a post-flight inspection. Initial plans focused on traditional repairs preserving original material, but after consultation, they shifted to additive manufacturing for a full replacement.
The 18th Maintenance Group printed two prototypes but faced issues achieving specifications. They contacted MALS-36, which operates the same printer type. Marines printed, delivered, and fit-checked two prototypes in under 12 hours.
Reviewing the Air Force technical data package, MALS-36 developed an optimized design that cut print time by two hours. Carrillo explained: “We were skeptical of the first design provided by [the MALS] due to the significant shorter print time compared to our first prints. Our techs learned that the duct’s orientation affects the necessity for the support structures, which allowed the Marines to reduce the duct’s print time without compromising its structural integrity.”
NAVAIR Additive Manufacturing Program Manager Theodore Gronda described the effort: “Here was a situation where a multi-million dollar aircraft was going to be sidelined for months due to the lack of a part in the supply system. The Air Force’s proactive, forward-leaning maintainers sought and obtained approval to repair the part using their on-site AM capability. 18 MXG was backstopped by MALS-36’s AM capability and they even got a better and quicker AM design out of the collaboration. This was truly a glowing example of a ‘One Team, One Fight’ effort.”
The improved printing parameters now appear in Air Force additive manufacturing publications for F-15 repairs fleet-wide. Carrillo added: “The duct’s new printing requirements are now part of the Air Force’s AM technical publications and will be used for similar repairs across the F-15 community. Cooperative and joint exercises with sister services and other stakeholders can help cross-pollinate ideas and methodologies, strengthen partnerships and increase force effectiveness.”
At Patuxent River, the NAVAIR team supports deployment of polymer-based systems to sites including Marine Aviation Logistics Squadrons and Fleet Readiness Centers. These enable production of non-critical and select critical parts using industrial-grade printers.
The base hosts extensive research facilities for aviation systems, including propulsion and materials engineering relevant to additive processes. Southern Maryland’s naval aviation community, centered around NAS Patuxent River, benefits from such advancements through sustained employment in engineering and maintenance roles supporting fleet readiness.
Additive manufacturing reduces reliance on distant depots, critical in contested environments. NAVAIR has expanded capabilities with the Naval Aviation School for Additive Manufacturing, training personnel across services in point-of-need production.
This cross-service repair demonstrates practical integration at forward bases like Okinawa, where MALS-36 supports Marine aviation and co-located Air Force units operate F-15s for regional security.