The call came through while Jim Cantrell drove his top-down convertible through northeastern Utah, the Rocky Mountains rising in the distance. He looked at his Motorola flip phone and didn't recognize the number. He picked up anyway.

The man on the other line spoke rapidly with an accent he couldn't place. Before Cantrell could get out more than a few words, the stranger was babbling about fossil fuels and space travel and the need to make humanity multi-planetary. "He's giving me his entire life philosophy," Cantrell says, "in like 30 seconds on the phone."

The person, as Cantrell eventually gathered, was Elon Musk. Not that the name meant anything to him; it was July 2001 and PayPal was just beginning to make its way into the mainstream. Cantrell, though tech savvy, had never heard of it.

Musk wanted to set up a meeting. "Where do you live?" he asked Cantrell. "I have a private plane. I can fly in tomorrow."

Cantrell was taken aback. He didn't know Musk. After his work overseas with the Russian space program, he'd become suspicious of strangers trying to get close to him. So he lied. "I fly internationally out of Salt Lake City on Sunday," he told Musk. This was pre-September 11, when a ticket wasn't a requirement to get through airport security. He told Musk to meet him in the Delta Crown Room. "That way," Cantrell says, "I knew he couldn't pack a gun."

The meeting, it turned out, was about Russian rockets. Cantrell had developed a reputation as someone who could get a hold of Russian space equipment. Musk wanted to build a company that sent payloads into space and, one day, could get to Mars.

It took a few months, but Cantrell eventually decided to join him and became one of the first four employees at SpaceX, a venture that Musk was financing solely by himself at the time.

A decade and a half later, SpaceX is valued at $25 billion and, according to Bloomberg, is the third-most valuable venture-backed private company in the world.

Cantrell, however, hasn't been along for the ride. Like Musk, he also saw an opportunity to build rockets in a way that hadn't been done before. His two-year-old startup Vector is betting that an assembly line-style of manufacturing will allow it to build and launch hundreds of small-cargo rockets annually--rather than the industry standard of handful of launches a year--and sell space on those rockets to small satellite companies for only a few million dollars per launch. In September, the company received a patent for an engine that uses an innovative type of fuel that is expected to make missions more cost effective.

"Building cars and building rockets are two very different worlds right now," Cantrell says. "I thought, how could we get [building rockets] to work more like a system? The market is big enough to sustain a lot of these small launches. If we can bring mass production to rockets, we can let the buyer go where they want when they want."

Investors seem sold on Vector's potential: Cantrell says the startup is in the process of closing a funding round of about $60 million, bringing its total raised to about $90 million. In the coming weeks, the Tucson, Arizona-based company will attempt its most sophisticated test launch to date. Its founder, an avuncular 52-year-old who can tell a half-hour story without pausing for a breath, says it will make its first commercial launch by the end of the year.

Getting here has been quite a journey.

A 'gray' area

Growing up in California, Cantrell wasn't really interested in space. "I was a machines and cars guy," he admits. At age 14, Cantrell took a job as a mechanic at an auto body shop. Four years later, he enrolled in the mechanical engineering program at Utah State University but his grades were only passable. During his senior year in 1986, he saw a poster on campus for a NASA-sponsored course during which students would design a Mars rover. The best designers would present their blueprints directly to NASA. Cantrell signed up. For weeks, instead of doing homework for his other courses, he worked on the design on the drafting board he kept in his bedroom.

Cantrell's group ended up competing nationally in Washington, D.C.--and winning. He soon landed a fellowship at NASA's Jet Propulsion Laboratory in California. While there, he helped design a mechanism called the Mars Snake, essentially a balloon that would bob along Mars's surface and collect samples. The French Space Agency decided to hire Cantrell to work on the project on its behalf, and it soon became a joint venture between France and the Soviet Union--the U.S.'s biggest rival.

"It was a gray area," Cantrell says. "Today I probably wouldn't be allowed to do it, but then I just did it. You ask forgiveness, not permission, right?"

Cantrell continued working with the Soviet space program until the USSR collapsed in 1991. The program fell with it, and Cantrell returned to the States.

Back home, he found it hard to land a job. "Nobody would hire me," he says. "They all saw me as a traitor." His meetings with the big aeronautics companies proved fruitless. "At Lockheed Martin," he says, "they would escort me into the friggin' bathroom and stand outside the stall. That's how dangerous they saw me."

Cantrell ended up returning to Utah State to work at the Space Dynamics Lab. His work kept bringing him back to Russia: After the 1995 Norwegian rocket incident, when Russia almost fired on the U.S. after mistakenly believing America was launching an attack, Cantrell helped the country improve its missile detection systems.

It was while he was working at the lab that Musk reached out to recruit him. "I was known as someone who knew how to do things cheap," Cantrell says. "And as a bit of a Russian expert, which was not really something you'd write home about. But it was an expertise."

The Musk meetings

Between 2001 and 2002, Cantrell made several trips to Moscow with Musk. The Russians, according to Cantrell, didn't take Musk seriously. Barely 30 years old, Musk had no formal training in rocketry, and he drove a hard bargain.

On the plane home after another failed meeting in Russia, Musk typed away on his laptop while Cantrell and Michael Griffin, who had joined the trip and later would be named NASA Administrator by President Bush, chatted over glasses of bourbon a few rows back. Musk turned around in his seat. "I think," he announced, "that we can build this rocket ourselves."

Cantrell and Griffin snickered.

"Fuck you both," Musk said. "I've got a spreadsheet."

Cantrell and Griffin burst into laughter. Now it was full-on comedy.

Musk passed his laptop to them. The pair saw tank weights, structure sizes, thrust calculations. As it turned out, the guy knew an awful lot about rockets, Cantrell thought. Musk had been reading up on his own and studying with John Garvey, an engineer who'd been building rockets in his garage in Southern California.

"We were trying to find something wrong," Cantrell says. "The interstage structures were a little light, but everything looked pretty good. It was essentially the Falcon One. Elon said, 'You know, when we get back to the U.S., we're going to start a company and build this rocket.' And that's how SpaceX started."

Over the next few months, Cantrell's main role was to use his network to pull in top talent, helping grow SpaceX from Musk's passion project into a 30-person company. He successfully recruited early employees like Chris Thompson, who became vice president of operations, and Tom Mueller, the company's chief technology officer of propulsion.

Then, less than a year later, Cantrell quit suddenly. "Elon yelled at me one too many times," he says. "I was done. And frankly, I just wasn't interested in what he was doing at the time. I really didn't think he treated this as a commercial activity." (SpaceX did not return requests for comment on Cantrell's accounts of the company's early days.)

Yet his time with Musk taught Cantrell an important lesson, one that he didn't fully absorb for many years: Do what you're passionate about, and do what you're inherently good at.

Cantrell spent the next few years consulting for the space industry. After the U.S. invaded Iraq and Afghanistan, much of his work began to focus on space warfare. Eventually, he grew disillusioned with the industry. "I became a conscientious objector to the war," he says. "I began to see my son's friends, who I'd known since they were little kids, coming back maimed and killed. I just couldn't take it anymore. I said, 'I'm done with the government.' " He returned to his first love, launching a car restoration company called Vintage Exotics.

Around 2013, Cantrell started noticing a large number of startups springing up in the space industry. When he read about Google buying five-year-old satellite company Skybox for $500 million the next year, it erased any doubts he had that the private sector was ripe for entry. "I began to see that space was getting fun again," he says. "People were building things and actually getting stuff done."

Cantrell saw particular potential in launching small satellites, also known as nanosats, that have become commonplace in recent years thanks to manufacturing upstarts like Spire, Planet Labs, and Capella Space. Cantrell sold his SpaceX stock (he won't say for how much), and in March 2016 he officially founded Vector with space vet Eric Bresnard and Garvey, the engineer who had taught Musk about rockets in his garage. Cantrell soon convinced some of his staff at the car company to join him. Within a year, the startup had raised more than $30 million from VC firms including Sequoia Capital and Shasta Ventures.

Ready for launch

Though he's long left government work, Cantrell's past sticks with him. When he visits me at Inc.'s office, he brings with him his publicist and a tall burly man whose role in the meeting isn't made entirely clear. The man grasps my hand with his giant paw and grunts his name to me through what appears to be a lip of chewing tobacco; then, during my interview with Cantrell, he pulls up a chair and sits behind me, facing my back.

Cantrell won't tell me more about the man or why he's tagging along. Separately, though, he tells me in passing that he's extra cautious after his time in Russia. He won't expand on why.

Cantrell would much rather focus on the future with Vector. The startup has already performed two test launches of its 40-foot-tall Vector-R rocket. In the coming weeks, it will "take the training wheels off," as Cantrell says, performing a launch without the use of fins to keep the flight path straight. The company hopes its first full-scale launch in Kodiak, Alaska follows soon after that, with its inaugural commercial flight coming later this year.

The driving principles behind Vector's business model are economies of scale: saving costs by manufacturing in larger volumes, much like in the automotive industry. Thanks to the team's car-building experience, it's applying assembly line tactics to build its rockets, creating a finished product in a matter of days, as opposed to the 12 months or more usually required.

The entire worldwide rocket industry currently makes only around 100 launches per year, according to Iain Boyd, professor of aerospace engineering at the University of Michigan and a scientific adviser to the U.S. Air Force. Boyd says the main factor that has prevented companies from seriously pursuing mass production of rockets isn't technical, but economic: The demand for more launches simply hasn't been there.

"It's all about cost," Boyd says. "Getting to space has been tremendously expensive." (To launch with SpaceX--the company that has revolutionized space travel by creating reusable, cheaper rockets--costs about $60 million.) But the calculus is changing. "It's now possible to build useful spacecraft, like nanosats, that are much smaller than ever before. That will require many more launches."

Still, Boyd says, while there are plenty of small satellite companies out there looking to hitch rides aboard rockets, there aren't enough yet to support an entire small rocket industry. "It's not like the market is there now and needs to be serviced," he says. "The potential is there. It's not guaranteed."

Cantrell looks at it somewhat differently: He thinks Vector will inspire more small-spacecraft companies. "The very existence of these rockets," he says, "stimulates demand for them."

The company also hopes it will gain a distinct advantage from its new liquid oxygen-propylene rocket engines, for which it received a patent in September and says no other company is using in operational launches. According to NASA program manager Timothy Chen, this type of propellant maximizes thrust while reducing costs. "It allows for a design that meets vehicle performance requirements while minimizing the volume needed," he says. "So in essence, it allows Vector to design a rocket with lowest cost possible."

A flight on the startup's smaller Vector-R will start at $1.5 million; the larger Vector-H will start at $3.5 million.

Plenty of rivals already exist. Rocket Lab, for one, launched its 56-foot Electron rocket for the first time earlier this year, carrying small satellites for two startups. Relativity Space is currently building 3-D printed rockets that it hopes will send up midsize payloads. And while SpaceX focuses primarily on clients with larger cargo, the company remains a reliable option and the industry leader for companies looking to launch satellites into space. placeholderplaceholderplaceholder

Vector has a minimum manifest of eight commercial flights next year, followed by 25 in 2020. By that time, though, Cantrell hopes the company will be performing 100 launches per year--or as many as will take place in the entire world in 2018.

Cantrell says Vector has signed or is close to signing letters of intent for launches valued at about $1 billion. The company, which has already grown to 130 employees, is in the precarious position of trying to grow quickly and box out any new competitors that might spring up--while also being careful not to eat through all its cash and scare away investors with its burn rate. "That," Cantrell says, "is the balance of terror that I live daily."