BAE Systems Regional Aircraft recently turned to 3D printing to make a thumbnail-sized pipe to keep approximately 500 jetliners flying.

The tiny pipe is a window breather, designed to keep passengers' windows from misting up. The issue was not a safety issue, but rather a "passenger perception issue," BAE spokesman David Dorman said.

However, anything that erodes passengers' confidence in the planes' safety, like misty windows, most likely would have been enough to ground the entire fleet, Dorman said.

These pipes were originally made for the BAE 146 regional jetliner by plastic injection molding, but the tooling originally used by the supplier was no longer available. New tooling would have cost over $23,000 and involved several months lead time. It would have also taken another two months to actually make the parts using traditional means.

So Philip Beard, Structures Support Manager at BAE Systems Regional Aircraft, contacted the central engineering team at the BAE Systems Military Air and Information business at Warton, Lancashire, who are busily experimenting with and building knowledge on 3D printing technology.

"Within two weeks our Warton colleagues had produced examples of the part and once we had used these to gain certification, they introduced us to a commercial 3D printing supplier who was able to produce the required quantity for us," Beard said. "Not only was there the significant time saving and the avoidance of the tooling cost, but the actual parts cost 60 percent less than the traditional method."

Overseeing the production process was considerably easier and cheaper with 3D printing than with the traditional molding process as well.

"Previously, we would have had people go down and visit the manufacturer for first article inspections of the moldings, but a lot of this is not necessary now because you are just sending files electronically, which simplifies the administration effort," said Graham Smith, head of business development at BAE Systems Regional Aircraft.

Approximately 300 of the window vent pipes were made and are ready for shipping from the company's warehouse.

"Having achieved this first breakthrough on the BAE 146 window breather pipe, we are now looking at a range of other 3D Printing opportunities to provide replacement parts across several different commercial aircraft types," Beard said.

"This technology offers a potential solution for aircraft parts that are prone to obsolescence, where tooling is unavailable, for quick turnarounds and also for small batch production. It may not be the solution for every part, but where appropriate, it provides a faster route from design to completed parts, meaning operators get the parts cheaper and quicker."

"Having achieved this first breakthrough on the BAE 146 window breather pipe, we are now looking at a range of other 3D Printing opportunities to provide replacement parts across several different commercial aircraft types," he added.

However, Beard and his colleagues are hesitant to lavish too much praise on 3D printing technology just yet.

"At the moment our imaginations are 50 years ahead of where the technology is. So, currently you can't print an entire aircraft wing, but it will happen," Beard said. "Maybe a mirror to look at is carbon fiber. If you go back 30 years, people were very comfortable making small parts in it but were not very comfortable making large parts. But today you have entire aircraft being made out of it," Beard said.

"I think we'll see something in parallel, it's just the timeframe that will be a lot less," he added. "So, the only thing now is technology keeping up with where we want to go."