SpaceX founder and CEO Elon Musk speaks with NASA administrator Jim Bridenstine, along with astronauts Victor Glover, Doug Hurley, Bob Behnken and Mike Hopkins, in front of the company's Crew Dragon capsule.

LOS ANGELES — SpaceX CEO Elon Musk and NASA Administrator Jim Bridenstine addressed concerns about safety for the company's crew capsule during a media briefing at SpaceX headquarters on Thursday.

Musk addressed an incident in April that destroyed the first SpaceX capsule, known as Crew Dragon, which had successfully returned from the International Space Station after a few days in orbit.

"You're trying to find extreme corner cases of where things go wrong," Musk said.

He noted that the primary mission was a success, as the additionally testing represented SpaceX looking to push the boundaries of the Crew Dragon capsule's systems and structure.

"If people had been on board that craft, they would have returned safely," Musk said of the test flight to the space station.

"You don't do tests because you think everything's going to be fine, you do tests to find out what's not going to be fine," Musk said. "I think there's a fundamental principle: Make sure you fail on the test stand so you do not fail in flight."

SpaceX issued a full statement on its website detailing the results of the investigation later in July, which revealed that a leaking component created a chain reaction of events that resulted in the explosion. The company recreated the incident at another facility and used the data to create a new system for Crew Dragon's thrusters, which SpaceX has been testing alongside NASA.

The two space leaders met on Thursday after Bridenstine toured SpaceX's facility, focusing on the Crew Dragon capsule that the company is building to fly NASA astronauts to the International Space Station (ISS). Bridenstine has recently added pressure on Musk and his team to safely yet quickly deliver on the government's investment in SpaceX, as the company won a $2.6 billion contract in 2014 for NASA's Commercial Crew program.

Commercial Crew is NASA's solution to once again launch U.S. astronauts from U.S. soil. Since the end of the Space Shuttle program in 2011, astronauts have flown to the International Space Station (ISS) aboard Russian Soyuz spacecraft — at a cost to NASA of more than $70 million per seat.

The first launches for the program have been pushed back from 2017 as delays mounted for SpaceX and Boeing, which also won $4.2 billion to build its own capsule for Commercial Crew. The most recent schedule update for the program was five months ago, in part because Bridenstine removed NASA's former leader of human spaceflight Bill Gerstenmaier from his role in July. The administrator said NASA needed more urgency in address inflating costs and delayed schedules for its key exploration programs.

In the meantime, Bridenstine has publicly pressured SpaceX to deliver on its side of the contract. In a statement the day before Musk gave a highly-anticipated update on the company's next-generation rocket called Starship, Bridenstine said "NASA expects to see the same level of enthusiasm focused on the investments of the American taxpayer." While Bridenstine said he was "looking forward to the SpaceX announcement," he emphasized that "Commercial Crew is years behind schedule," adding that "it's time to deliver."

Bridenstine tweet

Although Bridenstine's statement spoke about Commercial Crew, he did not mention Boeing at the time, which is also behind schedule. Asked by The Atlantic whether he was singling out SpaceX, Bridenstine noted that he has "been critical of all contractors that overpromise and underdeliver."

During the Starship presentation, Musk responded to Bridenstine.

"From a SpaceX resource standpoint, our resources are overwhelmingly on Falcon and Dragon. Let's be clear, it was really quite a small percentage of SpaceX that did Starship," Musk said, noting that he believes less than 5% of the company's total workforce had been working on the new rocket.

While Musk has said SpaceX will be ready for its next milestone, known as an inflight abort test, in about 10 weeks, Bridenstine has remained skeptical. Testing the updates to Crew Dragon following the explosion, as well as capsule's parachute systems, will take at least three more months, Bridenstine estimated.