A parachute on a SpaceX Dragon capsule didn't open as fast as expected as the craft descended to Earth

• A parachute on a SpaceX Dragon failed to open as expected as the capsule descended to Earth in January.
• It's the second time the apparent fault has occurred.

One of the four primary parachutes on a SpaceX Dragon craft took longer than expected to deploy as the capsule descended to Earth in January, a NASA official said Friday.

It's the second time the apparent fault has occurred, following a similar incident involving a Dragon craft in November.

NASA and SpaceX said they don't believe the slow-deploying parachute posed a safety risk in either incident, but the issue will be "thoroughly investigated." They said they will see "if we can get smarter about how these systems operate so we can make sure that, yes, this really is a nominal operation of this four-chute system, or maybe there's something here that's going on that's different."

Per Space News, NASA program manager Steve Stich said: "This lagging parachute phenomenon is something we see with these large ringsail parachutes." He suggested the phenomenon could be due to the three other canopies shading one of the others "and it just struggles to inflate at times."

Per The Verge, SpaceX executive William Gerstenmaier said that despite the delay in the parachute opening, it still slowed down the Dragon capsule. He added: "This is more of a learning exercise of how we can improve our design and engineering understanding of parachute operation."

The Dragon spacecraft is equipped with six parachutes altogether, including two that stabilize the craft upon re-entry. Four primary chutes then slow the vehicle down in its descent, according to SpaceX's website.

Dragon can carry up to seven astronauts. It can also carry cargo.

In April, SpaceX plans to send another crew of astronauts to space using a Dragon capsule and Falcon 9 launch vehicle.

Insider's Kate Duffy reported Friday that SpaceX aims to launch Falcon 9, its most-used spacecraft, once a week on average through 2022.