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This Tiny 3D Printed Jet Engine Could Have Big Promise

Ozy

Call it the little engine that could. Last year, a team of engineers at GE Aviation’s Additive Technology Center built an almost entirely 3D printed miniature jet engine — a backpack-size powerhouse that hits 33,000 rotations per minute.

While this little guy — it measures 1 foot, 8 inches — isn’t going to propel a commercial airliner anytime soon, it did demonstrate that a powerful, functioning engine built mainly from 3D printed parts isn’t a flight of fancy so much as the future of flight.

Additive manufacturing is hardly new to aviation. Parts of full-size aircrafts already incorporate 3D printed parts. CFM’s LEAP engine — a best-seller since it entered into service last year — has 3D printed fuel nozzles. In April, Reuters reported that Boeing would start using 3D printed parts for structural components of its 787 Dreamliner. Though petite, GE’s mini engine could have big implications. It represents the promise that one day, you could be sitting on a plane, and the engine keeping you in the sky will have been entirely 3D printed.

Coolness factor aside, 3D printed jet engines are considerably lighter, and reducing the weight of an aircraft has the knock-on effect of reducing the amount of fuel needed to keep a plane in the sky — and less fuel means a more cost-effective flight, and less emissions.

Boeing estimates that by incorporating additive manufacturing in the production of up to 1,000 Dreamliners, the company could potentially reduce costs by up to $3 million per plane. Imagine the savings if the technology were rolled out on a greater scale.

Using 3D printing to manufacture parts also means less material waste, which further reduces the cost and complexity of production. For example, the process GE used to print its mini engine — direct metal laser melting, or DMLM — involves melting metal powder layer upon layer and building a part from the ground up, rather than cutting it from one large piece of material.

Additive manufacturing also means a quicker, more custom design. GE says that 3D printing fuel nozzles for the LEAP engine allowed engineers to reduce the number of brazes and welds in the design from 25 to just five.

“You get speed because there’s less need for tooling and you go right from a model or idea to making a part,” says Matt Benvie, a spokesman for GE Aviation. “You can also get geometries that just can’t be made any other way.”

There are still limits to what 3D printing can achieve, of course. The new technology is not yet as fast nor as cheap as hoped; it took GE years to build a small, simple prototype. The materials needed for 3D printing can sometimes be too expensive for mass production. And we’re not yet in a place where 3D printed parts are coming out perfect — post-processing work is often required.

Still, for aircraft manufacturers, the benefits of eventually 3D printing most, if not all, aircraft parts are too great not to pursue. Airbus has gone so far as to say the technology could reduce both raw material and energy used in production by 90 percent; it has also been reported that 3D printing all the possible components of an A350 would reduce the weight of the aircraft by more than a ton. For a feel of just how much fuel that would save, consider that back in 2014, Virgin Atlantic slimmed the design of its meal trays to trim 300 pounds of weight per flight — enough to save millions of dollars on fuel (not to mention reducing carbon emissions).

Even more interesting, it could be that size does matter. In December, Pune, India–based market research company ReportsnReports said miniaturizing aircraft components through 3D printing would be key to improving fuel efficiency and operating costs in years to come. Perhaps the future is all about thinking small.