To keep their fleets of planes running smoothly, airlines need ready access to replacement parts. But stocking the tens of thousands of parts that make up an aircraft interior is an expensive proposition—especially given the small quantities that are often involved. Now, one company is using a 21st century technique to cut the cost of obtaining replacement parts. Air New Zealand is using 3-D printing—also known as additive layer manufacturing technology—to make the fold-down cocktail trays that form part of its "business premier" passenger seats.

The Kiwi company launched the project through a collaboration with Auckland University of Technology, whose 3-D Printing Lab works with students, staff, and industry on projects that demand quick production of complex three-dimensional prototypes and on-demand manufacturing.

"Aircraft interiors are made up of tens of thousands of parts," Air New Zealand Chief Operations Officer Bruce Parton said in a release. "Not only can't we hold stock of every replacement part we might need, we often only require a small number of units, which can be really expensive to produce using traditional manufacturing methods and can involve frustrating delays while a replacement part is delivered."

The airline hopes to start installing its 3-D-printed cocktail trays on aircraft soon and is already exploring new applications for additional components.