SpaceX is now an established company, with close ties to NASA, helping make Mr Musk one of the richest people on the planet. However back in 2008 the company was struggling following three unsuccessful attempts to launch Falcon 1 into orbit.
The story of SpaceX’s early years, including the fourth successful launch of Falcon 1, is included in the new book ‘Liftoff’.
The work, written by Ars Technica senior space editor Eric Berger, includes the story of how one engineer prevented a potentially catastrophic accident ahead of its launch.
Mr Musk later admitted SpaceX wouldn’t have survived as a company had this launch failed.
According to Newsweek he’d given his engineers just two weeks to organise a successful launch into orbit.
Ahead of the launch, SpaceX hired a military aircraft to transport its rocket to the launch site by Hawaii.
However, as the plane came in to land engineers realised its fuel tank was having difficulty adjusting to the pressure difference.
Business Insider acquired an early copy of Liftoff in which Mr Berger said those on board heard a “terrible popping noise”.
In response, SpaceX operations manager Anne Chinnery urged the engineers to move to the front of the rocket fearing the fuel tank could explode.
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He commented: “I messed up the first three launches, the first three launches failed.
“Fortunately the fourth launch—that was the last money that we had—the fourth launch worked, or that would have been it for SpaceX.”
Mr Dunn became SpaceX senior vice president of production and launch.
When he left the company to join another rocket firm last year Mr Musk paid him a personal tribute on Twitter.
The business tycoon tweeted: “Zach made a significant contribution to SpaceX & is a friend.
“I wish him well as he tried something new.”
In 2020 SpaceX delivered four astronauts to the International Space Station (ISS) from NASA’s Kennedy Space Centre.
This was the first time US astronauts had been taken to the station by an American rocket since 2011.
NASA’s Space Shuttle programme was ended in 2011 following the Space Shuttler Columbia disaster.
For a number of years American astronauts could only reach the ISS using Russian rockets.