Few have more riding on SpaceX’s next launch than Iridium Satellite Communications.

The McLean-based company has spent $3 billion to build a fleet of new, state-of-the-art satellites that would replace an aging constellation that’s been in orbit for years. The company has hired SpaceX for seven missions over the next year to launch dozens into orbit.

The only problem: SpaceX’s Falcon 9 rocket has blown up twice. The company is currently grounded again for the second time in two years. And even though SpaceX’s Elon Musk has said the company should fly by mid-December, the investigation into the explosion on Sept. 1 isn’t yet complete and the Federal Aviation Administration hasn’t yet given it the green light to fly.

But Matt Desch, Iridium’s chief executive, said he is not worried. In an interview, he said he was heartened the investigation to date and by recent comments by Musk, who said that the company has discovered the cause of the explosion on Sept. 1.

“We’ve been privy to the thinking and the analysis and the data involved at a very deep level,” Desch said. “So, yes, we know why he is saying what’s he’s saying and concur that they have found the issue. We’re encouraged, too, that it was procedural…We are back on the path for a first launch and, yes, I feel very confident that the issue that was found won’t be repeated for our launch.”

Still, he said on launch day, “I might be in a corner rocking back and forth.” Not out of fear for the rocket, but more because it’s always nerve racking “when you see 10 of your precious babies going into orbit.”

On Sept. 1 a Falcon 9 rocket blew up on a Cape Canaveral launch pad while it was being fueled ahead of an engine test fire. Musk said on CNBC Friday that the cause of the explosion was “a really surprising problem that’s never been encountered before.”

SpaceX has been super cooling its liquid oxygen fuel, a process that makes it more dense, allowing the rocket to then carry more fuel. But apparently the propellant got so cold it turned solid, Musk said, without elaborating on how exactly that could lead to an explosion.

“This was the toughest puzzle that we’ve ever had to solve,” he said.

With an aging constellation of 66 satellites now in orbit, Iridium is eager to replace them with the new fleet. The company’s satellites provide an array of services, from communications and tracking for service members in war zones, to delivering Internet and mobile phone service to remote areas around the world and at sea.

The new constellation will allow the company to offer airline tracking from space. It will also help the company with its fastest-growing market—the so-called Internet of Things—connecting machine to machine, so they can communicate on their own.