A350 Composite Door Surround

As my other composite development project was approaching completion, we launched an even larger and more ambitious Titanium to Composite redesign. The A350 has four pairs of passenger doors plus a cargo door, all but one of which had composite edge frames. Our project was to design and build an updated Passenger Door Surround (PDS) using composite frames instead of the old titanium ones. This would save a significant amount of cost and weight along with modernizing the PDS3 and aligning its design with the other door surrounds.

We started the research and development activity that would be required to design, test, and eventually build a production-ready process in early 2020. Little did we expect that we would spend the majority of our R&D campaign working from home due to pandemic restrictions.

Even with hard constraints, our team plugged away, creating and modifying tools, running simulations, and testing different concepts and iterations. After more than a year of expert involvement, we were finally ready to transfer the process to our Kinston, North Carolina manufacturing plant and begin build trials.

While it definitely wasn’t an easy process, with our process experts and manufacturing gurus working side-by-side, we were able to set up the Kinston factory to build test parts which passed their requirements with flying colors and start building production frames for flight.

Composite edge frame in mid-ply layup, and the assembled door surround structure installed in a fuselage

In the end, after a multi-year, 10-figure effort, Spirit Kinston was able to build the largest and, in our opinion, best performing composite edge frame in the world. One of our measurement experts said what we had achieved on the project was something he’d never seen before, and that we were treating this complex composite structure like “black aluminum.”

Our edge frames are now flying and will eventually become the standard on all A350 units going forward. We saved over $100,000 in cost and 50kg of weight per aircraft, improving Spirit’s margin while also reducing the A350’s carbon footprint. And, just as special to me, we created something truly world-class in the process.