The US Army is hoping to 3D print replacement parts for its Black Hawk helicopter. U.S. Army photo by Sgt. Christopher Harper.

Imagine you’re in a battlefield situation — your combat unit’s supply lines are under attack, and the threat of being cut off altogether looms large.

Enter 3D printing technology — luckily you have deployed an archive of 3D models, a few printers, and a supply of powdered feedstock. Potentially, you could now 3D-print your own repair parts on demand.

Experts say the latter could liberate frontline units from logistical challenges and make them much more maneuverable in the fast-faced all-domain operations envisioned for future wars, and, save costs dramatically.

This is why Wichita State University in Kansas is taking an Army Black Hawk helicopter apart piece by piece. They are scanning each component carefully to create a detailed three-dimensional model that could be be used for 3D printing, the head of Aviation & Missile Command told Breaking Defense.

“We have a UH-60 Lima [that] we are currently disassembling,” AMCOM chief Major General Todd Royar explained. “[For each] component, they’re scanning it, making a 3D model of it, putting it in a CAD [Computer-Aided Design] file… We’ll start to get those back in a couple of months.”

Just how many different components are there in the UH-60L model of the Black Hawk?

“We expect to probably get about 20,000 structural parts, -ish, out of that,” Royar said. “We’ll take a look at it and evaluate every one” to see whether it can be safely and economically replaced with a 3D-printed version, Breaking Defense reported.

Many industries have already benefited from 3D printing, including aviation, where aircraft now feature 3D-printed parts throughout their airframes. Several air forces have followed suit, and army counterparts are now doing the same for their combat vehicles.

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However, although 3D printers are simple enough for schoolkids to use, if you’re trying to print a part that’ll hold up in battle or in flight, you can’t just eyeball the original and guesstimate the dimensions, Breaking Defense reported.

Now, companies that use modern digital design techniques produce 3D models of their new parts as a matter of course, and they often share these with the government.

Tank-Automotive Command (TACOM) has such data files for the new Infantry Squad Vehicle, for instance, and plans to 3D print some parts as a proof of concept, Breaking Defense reported. But digital models simply don’t exist for vast inventories of older parts, some dating back decades.

To make a model where none exists, you need to use a specialized scanner – some are handheld, others mounted on robotic arms – to map each part in three dimensions.

That’s just one step in a complex process, explained Brigadier General Darren Werner, commander of TACOM, which oversees the Army’s new Advanced Manufacturing Center of Excellence at Rock Island Arsenal.

You have to study and analyze parts to identify which might be suitable for 3D printing, because not everything is, Breaking Defense reported.

For example, some components might come under so much stress that they’re best machined from a single, solid block of metal, using traditional “subtractive” manufacturing, instead of additive manufacturing that builds objects up layer by printed layer.

They might also need to be made of special materials, or specially treated, in ways that 3D printers can’t yet handle. Or they might be just too big for the available printers to produce.

Other parts might be possible to print but cheaper to make the old-fashioned way — so there’s an economic element of the analysis, not just an engineering one, Breaking Defense reported.

Once you’ve identified a suitable part, you need to certify that the 3D-printed version will be safe and reliable. That’s one of the most demanding and time-consuming parts of the process, the generals at the press conference agreed, especially for aircraft where components must meet Army and FAA  flight-safety standards.

“It’s relatively easy, once you have a 3D model, to print something,” said Royar, who’s the Army’s airworthiness certification authority, “but to ensure that it meets the qualification standards, that’s hard.”

As for cost savings, Popular Mechanics reported the US Air Force will save millions of dollars and airmen spared the dirty work of crawling inside fuel tanks, all by using a simple tool invented by a serving airman.

The pressurized leak detection cup will cut the the number of hours needed to detect for fuel tank leaks by up to 75%, saving the service more than a million dollars a year. To top it off, the new tool is 3D printed and costs just $15 to produce.

The USAF, which operates a fleet of aging Cold War-era aircraft, is especially vulnerable.

According to Wired, the average Air Force aircraft is 23 years old. Every quarter, the military branch sees 10,000 part requests go unfilled, despite its readiness to pay an exorbitant amount of money to replace bits and bobs that once cost pennies — try $10,000 for a toilet seat cover in a C-17 Globemaster III.

Talk about flushing money down a toilet. By the way, the cost of a 3D-printed toilet seat cover is $300.

The USAF has also 3D-printed its first metal part for a jet engine.

The replacement part, made for the engine that powers the B-52 Stratofortress bomber, will keep the plane flying until new engines are fitted to the aging jets in the late 2020s, Popular Mechanics reported.

— with files from Breaking Defense, Popular Mechanics, Wired and AZO Materials