For Marcy Fisher, one of the global pandemic’s biggest and most urgent recent headaches involved a small piece of elastic.

On March 20, Fisher, a Ford Motor lifer who normally oversees the automaker’s global body exterior and interior engineering, became one of about 200 Ford executives and employees facing an urgent new mandate: How could the country’s largest automakers, their massive production lines idled by the threat of spreading infections, pivot into producing desperately needed medical supplies?

Crosstown rival General Motors had already jumped into action, hammering out a partnership with ventilator specialist Ventec Life Systems. Ford CEO Jim Hackett and his deputies consulted with experts at the Mayo Clinic, a medical supplier, and the White House, which was agitating—loudly—for the automakers to get involved. Soon they were strategizing with their counterparts at General Electric and 3M.

While those more complicated devices would take weeks or months to produce, Fisher’s team started with one of the most basic of supplies: the plastic face shields that medical workers use to protect themselves from patients’ infected coughs and other airborne health hazards. Within a day she had a viable design and was talking to suppliers about getting the material to make hundreds of thousands more. The plastic part was simple enough. But when it came to the elastic band that secures the shield onto someone’s head, Ford “ran into a big industry shortage,” Fisher recalls.

The solution, when it came, was gloriously banal. At 4 a.m. on March 26, one of Ford’s suppliers opened up its plant and started extruding a version of the flexible rubber tubing, or weather strips, that you’ll more normally find sealing car doors and windows. “By 8 a.m. we had a prototype,” Fisher says. Within hours, her team was dropping off samples at local hospitals for ER doctors to vet. Within days, Ford had manufactured 100,000 of the final products; by mid-April, it was making 1 million per week. And the elastic substitute? “It’s completely innovative, and it totally works,” says Erin Brennan, an emergency physician at a Detroit hospital, who tested the face shields. “This team has been awesome.”

But that was the easy part. The rest of Ford’s high-speed efforts to turn itself into a medical manufacturer—including a promise to produce 50,000 ventilators by July 4—will be even more complicated and subject to much greater scrutiny.

Ford’s “Project Apollo,” named for the scrappy rescue of the Apollo 13 astronauts, involves cross-industry partnerships with GE, 3M, and many smaller suppliers, as well as the willing participation of more than 750 United Auto Workers members who will operate Ford’s retooled factories. Besides face shields and ventilators, it will yield medical supplies including masks, gowns, and respirators. Few of these devices are simple to design, source components for, or manufacture—especially under the pandemic’s life-and-death deadlines.

“Lives are at stake,” says Jim Baumbick, the Ford vice president of enterprise product line management, who’s overseeing the automaker’s efforts to make medical supplies for COVID-19. “A lot of these machines are incredibly complex, and adding capacity takes time. And time is the enemy.”

That’s especially true for the sophisticated and urgently needed ventilators that help critically ill patients breathe. Traditionally made by a handful of medical-device specialists, ventilators require many more components and are much more regulated than face shields.

In an attempt to streamline the process, Ford and GE decided to focus on an FDA-approved, relatively simple version produced by a small Florida company, Airon. “The key factor is speed and getting as many ventilators as possible to clinicians treating COVID-19 patients,” Tom Westrick, GE Healthcare’s chief quality officer, says in an emailed statement.

It’s completely innovative, and it totally works.

Even these ventilators require about a month of sourcing, design, and regulatory conversations before Ford’s factory workers at the Rawsonville plant in Ypsilanti, Mich., can start producing them. Each Airon machine has up to 350 parts, which Adrian Price’s manufacturing team spent a weekend taking apart and 3D-scanning, before starting to look for ways to replicate them on a massive scale. (One substitution: adapting a timer valve usually used in Ford vehicles’ powertrains.)

“When we build a car or truck, the first thing for us as a manufacturing team is to figure out how to build one, and then how to build a few, and then how to build them at rate,” says Price, Ford’s director of global manufacturing core engineering and the executive in charge of its new ventilators, in early April. “And that’s really the process that we’ll be going through over the next couple of weeks.”

Ford expects its internal ventilator production to start the week of April 20, with a goal of making 1,500 ventilators by the end of April; 12,000 by the end of May; and 50,000 within 100 days. (GM will supply 6,000 by the end of May and 30,000 by the end of August.) Still, the effort may not be enough, as experts are predicting the country will need another 14,000 ventilators by mid-April.

“We’re too late to the party,” says Marcus Schabacker, a physician and the head of ECRI, a nonprofit focused on medical devices and patient safety. No matter how many ventilators are actually produced in the next few months, there are other hurdles that no manufacturer can solve, he says—including an equally dire shortage of trained health care personnel that can use them.

The UAW workers who have volunteered to risk the virus and manufacture the ventilators will be working at social-distance levels, and Ford says it is considering new, as-yet-unspecified technology to protect them. But that’s not a guarantee, of course—and the last two questions are even trickier. Baumbick says, “We haven’t spent any time talking about cost,” and adds that Ford is working with a coalition of hospitals and government agencies and officials, including FEMA, the CDC, and the White House, to decide where its medical supplies will go.

“It’s very good and very positive that these companies are stepping forward,” adds Julie Letwat, a health care attorney with McGuireWoods in Chicago. “But the devil’s in the details. Will they have enough workers? Who’s paying for these? How will they be distributed?”

The federal government is also getting more actively involved. On April 8, the U.S. Department of Health and Human Services announced that it had given GM a $489 million contract to deliver 30,000 ventilators by the end of August. By then, Ford may be supplying a vast array of medical supplies and personal protective equipment. On April 13 the company announced that it has started making masks, and is turning airbag material into reusable gowns.

Now that the face shields are flying out of its factories, Fisher has turned her focus to a much more complex device: a battery-powered, air-purifying respirator. Internally, Ford calls it a “scrappy” version of a PAPR, the hood-and-air-hose devices that doctors sometimes wear with or in lieu of the N95 masks that are in such short supply. “We thought it was going to be an area of unmet need,” Fisher says. “And it looked like something that not everybody could do, in an area where we have a lot of engineering depth.”

The PAPR design, which Ford has adapted from and is developing with advice from 3M, also required regulatory conversations and testing before Ford could start production on April 14. The company says that it will assemble 100,000 or more of the PAPRs at its Vreeland facility near Flat Rock, Mich.

“Things are very fluid right now,” Fisher said earlier in the month, echoing a common refrain during this coronavirus spring. “It’s just moving so fast.”

Going to war with the virus

In the 1940s, Ford and General Motors switched their factories over to manufacture tanks and airplanes for World War II. Now both are invoking that comparison to make supplies to fight COVID-19, as are some of their fellow automakers and leaders of many other industries. What they’re making:

Ford

Ford is already producing 1 million plastic face shields a week and has promised 50,000 Airon ventilators by July. It’s also making a version of 3M’s respirators and is helping 3M and GE ramp up their own production of respirators and ventilators.

General Motors

General Motors has promised the federal government 30,000 ventilators by the end of August, in partnership with medical-device specialist Ventec Life Systems. GM is also working on surgical masks and says it could eventually make 50,000 a day.

Xerox

Xerox is partnering with Vortran Medical Technology to make up to 200,000 disposable, non-ICU ventilators a month by June.

Dyson

Dyson has promised the U.K. government 10,000 of a newly designed ventilator, and founder James Dyson has said he will donate another 5,000 internationally.