SpaceX has launched the world’s first crew of “amateur astronauts” on a private flight to circle Earth for three days.

Wednesday night’s successful launch marked the most ambitious leap yet in space tourism. It’s the first chartered passenger flight for Elon Musk’s space company and the first time a rocket streaked toward orbit with a crew that contained no professional astronauts.

“It blows me away, honestly,” the SpaceX director, Benji Reed, said on the eve of launch from Nasa’s Kennedy Space Center. “It gives me goosebumps even right now to talk about it.”

Leading the flight is Jared Isaacman, 38, who made his fortune with a payment-processing company he started in his teens. Isaacman is the third billionaire to launch this summer, following flights by Virgin Galactic’s Richard Branson and Blue Origin’s Jeff Bezos in July.

Isaacman is joined by Hayley Arceneaux, 29, a childhood cancer survivor who works as a physician assistant at St Jude Children’s Research Hospital in Memphis, Tennessee. Isaacman has pledged $100m of his own money to the hospital and is seeking another $100m in donations.

Also along for the ride are the sweepstakes winners Chris Sembroski, 42, a data engineer in Everett, Washington, and Sian Proctor, 51, a community college educator in Tempe, Arizona.

Arceneaux is set to become the youngest American in space and the first person in space with a prosthesis, a titanium rod in her left leg.

The passengers will spend three days orbiting Earth at an unusually high altitude of 357 miles (575km) – 100 miles (160km) higher than the International Space Station – before splashing down off the Florida coast this weekend.

While Nasa has no role in the process, its managers and astronauts are rooting for the flight, dubbed Inspiration4.

“To me, the more people involved in it, whether private or government, the better,” said the Nasa astronaut Shane Kimbrough, who is nearing the end of his six-month space station stay.

Isaacman, an accomplished pilot, persuaded SpaceX to take the Dragon capsule higher than it’s ever been. Initially reluctant because of the increased radiation exposure and other risks, SpaceX agreed after a safety review.

“Now I just wish we pushed them to go higher,” Isaacman told reporters on the eve of the flight. “If we’re going to go to the moon again and we’re going to go to Mars and beyond, then we’ve got to get a little outside of our comfort zone and take the next step in that direction.”

Isaacman is picking up the entire tab for the flight but won’t say how many millions he paid.

Though the capsule is automated, the four Dragon riders spent six months training for the flight to cope with any emergency. That training included centrifuge and fighter jet flights, launch and re-entry practice in SpaceX’s capsule simulator and a grueling trek up Washington’s Mount Rainier in the snow.

Four hours before liftoff, the four emerged from SpaceX’s huge rocket hangar, waving and blowing kisses to their families and company employees, before they were driven off to get into their sleek white flight suits. Once at the launch pad, they posed for pictures and bumped gloved fists, before taking the elevator up. Proctor danced as she made her way to the hatch.

SpaceX’s next private trip, early next year, will see a retired Nasa astronaut escorting three wealthy businessmen to the space station for a weeklong visit. The Russians are launching an actor, film director and a Japanese tycoon to the space station in the next few months.

Once opposed to space tourism, Nasa is now a supporter. The shift from government astronauts to non-professionals “is just flabbergasting”, said the former Nasa administrator Charles Bolden, a former space shuttle commander.

“Someday Nasa astronauts will be the exception, not the rule,” said Cornell University’s Mason Peck, an engineering professor who served as Nasa’s chief technologist nearly a decade ago. “But they’ll likely continue to be the trailblazers the rest of us will follow.”