Today, Boeing tested a key system on its new passenger space capsule, the CST-100 Starliner, a major milestone that gets the company ready for the vehicle’s first flight to space. Today’s test fired up the emergency abort engines on the capsule, which are designed to carry the spacecraft to safety if there is some major issue during a future launch. The entire test lasted for just about 95 seconds.

For the last five years, Boeing has been developing the CST-100 Starliner to transport astronauts to and from the International Space Station as part of NASA’s Commercial Crew Program. The vehicle is meant to launch on top of an Atlas V rocket, which is manufactured by the United Launch Alliance, and carry up to seven crew members to orbit at a time. But before today, the Starliner had yet to actually see space — or see much air at all.

In fact, today’s event was the vehicle’s first big test flight for Starliner. Boeing performed what is known as a pad abort test, which demonstrated Starliner’s ability to escape a dangerous situation during a launch. The spacecraft is equipped with four launch abort engines that can ignite if the rocket carrying the capsule starts to break apart on the launchpad or just after takeoff. These engines carry the spacecraft up and away from the malfunctioning rocket, before Starliner lands using parachutes. Boeing says that Starliner’s engines can kick into action either on the launchpad or during the ascent to space.

No actual rockets were involved with today’s test, though, as all eyes were on the Starliner capsule. At the White Sands Missile Range in New Mexico, Boeing ignited the Starliner’s launch abort engines on the ground, which carried the capsule up and away from its pad at Launch Complex 32. The team suffered a setback when only two of Starliner’s three main parachutes deployed, but the two parachutes were enough to lower the spacecraft gently to the ground. A set of airbags also popped out underneath the vehicle to cushion its fall onto the desert floor.

“Today’s pad abort test was a milestone achievement for our CST-100 Starliner team, for NASA, and for American human spaceflight. We will review the data to determine how all of the systems performed, including the parachute deployment sequence.” Boeing spokesman Todd Blecher said. “It’s too early to determine why all three main parachutes did not deploy, however, having two of three deploy successfully is acceptable for the test parameters and crew safety.

Even with the parachute issue, Boeing is hailing this test as a win. The company has suffered some setbacks with its launch abort engines before. In June 2018, some of the abort engines didn’t close properly during a test fire at White Sands, causing some propellant to leak out unexpectedly. The company says it has since made some design changes, which have fixed the problem. Boeing’s rival in the Commercial Crew Program, SpaceX, has also been having issues with its own abort engines, which led to the explosion of the company’s own capsule, the Crew Dragon in April.

Boeing needed this test to go well in order to perform an even bigger flight in the months ahead: Starliner’s first uncrewed trip to the International Space Station. That launch is currently scheduled for December 17th, though it’s possible the date could change, as timelines for the Commercial Crew Program have changed plenty of times before. At the moment, however, Blecher says: “At this time we don’t expect any impact to our scheduled Dec. 17 Orbital Flight Test. Going forward we will do everything needed to ensure safe orbital flights with crew.”

Once Boeing successfully demonstrates Starliner’s ability to travel to and from the station, then it can prepare for its biggest milestone: sending NASA astronauts Mike Fincke and Nicole Mann and Boeing astronaut Chris Ferguson to the International Space Station on Starliner’s first crewed test flight.

Update November 4, 12:22PM: This story has been updated to include a statement from Boeing.