Saab has flown a 3D printed replacement part on the outside of a Gripen fighter plane for the first time. The test flight over the company’s Linkoping, Sweden facility on March 19, 2021 may pave the way for the use of 3D printed parts for repairs on the battlefield.
When talking about military affairs, it’s really easy to focus on flashy topics like fighter jets and forget that there is a very long line of support staff for every Top Gun pilot. In fact, any combat unit on land, at sea, or in the air is just the very sharp point of a very long logistic spear.
Unsurprisingly, one of the biggest and most persistent problems is keeping combat aircraft away from forward-operating bases by making sure they have enough spare parts to fix combat damage or inevitable wear and tear. This is not always possible, so mechanics often have to improvise or steal parts from multiple aircraft to keep an aircraft running.
To address this issue, Saab and the AMEXCI consortium have been working on the Battlefield Damage Repair project since 2018, which uses 3D printing technology to quickly produce replacement parts in the field so that an aircraft can either complete its mission or fly back to an aircraft maintenance base for more extensive repairs.
The replacement flap was printed from a nylon polymer
For the recent test, a maintenance hatch on the outside of the fuselage was replaced with a 3D printed version. Since there was no digital model for the component, a bespoke scan had to be performed before the part was printed from PA2200 nylon, a high quality, high strength polymer that is not only inexpensive but also chemically and UV resistant. By scanning the part, it was possible to make a copy that would fit that single airframe just like the original.
The next step in the testing program is to make sure the 3D printed replacement part meets airworthiness requirements and to find alternatives to PA2200 that are more flexible and better withstand the freezing air of high altitude flights. At the same time, the development team is working on the production of a 3D printing system that can be built into a container to make bases available for forwarding.
“The initial hatch inspection after the flight was very positive and showed that no visual structural changes had occurred during the flight,” says Håkan Stake, contract manager for Gripen C / D support and manager of the development project. “The potential of this approach means that on-site maintenance personnel can have access to customized replacement parts, eliminating the need to resort to emergency fixes or cannibalizing other broken aircraft for their parts, while further reducing the number of parts that are needed in a mission This also reduces the uptime that is lost in repairs. “