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The world’s most frequently launched rocket — the SpaceX Falcon 9 — is cleared to fly again, federal regulators announced Friday evening, putting the vehicle back on track for two high-profile human spaceflight missions.
The Federal Aviation Administration, which licenses commercial rocket launches, grounded SpaceX’s rocket on August 28, after part of a Falcon 9 rocket booster exploded while attempting to land. Just two days later, the agency said it has cleared the rocket to return to flight.
“The SpaceX Falcon 9 vehicle may return to flight operations while the overall investigation of the anomaly during (Wednesday’s) mission remains open, provided all other license requirements are met,” the agency said in an emailed statement. “SpaceX made the return to flight request on Aug. 29 and the FAA gave approval on Aug. 30.”
Falcon 9’s clearance comes as SpaceX has two pivotal missions on its manifest. The company is slated to launch a mission called Polaris Dawn that will carry a crew of civilian space travelers on an ambitious journey to attempt the first commercial spacewalk. The launch has already been delayed due to a ground systems issue and forecasts of inclement weather.
And as soon as late September, SpaceX is set to launch two NASA astronauts to the International Space Station on Crew-9, a mission that — after a monthslong rotation — aims to ultimately bring home Boeing Starliner’s test flight crew in 2025.
NASA astronauts Suni Williams and Butch Wilmore have been in limbo on the orbiting laboratory since their Starliner flight in early June.
Falcon 9’s rare failures
Failed Falcon 9 booster landing attempts — such as the one that occurred on Wednesday — do not affect the overall success of a SpaceX mission. The company attempts the maneuver solely so it can refurbish and reuse the rocket boosters, a practice that brings down the cost of each flight, according to SpaceX.
About a decade ago, SpaceX routinely tried and failed to land its boosters after flight. The company even shared a gag reel of the explosions in 2017.
In recent years, however, Falcon 9 boosters routinely have found their footing upon return to Earth.
The Falcon 9 booster that exploded August 28 had been refurbished and flown 22 times before it crash-landed. The mission it launched the day of the mishap, however, was ultimately successful, delivering a batch of internet-beaming Starlink satellites into orbit.
But that explosion marked the second time in two months that an anomaly prompted the FAA to open an investigation into the Falcon 9, which also has a history of hundreds of flights that have gone off entirely without issue.
In July, however, as a Falcon 9 was delivering another set of Starlink satellites into orbit, the upper stage of the rocket — which is distinct from the bottommost booster — failed abruptly mid-flight.
The satellites did not enter their intended orbit, and the overall mission was a failure.
SpaceX later revealed that an oxygen leak occurred while the second stage of the rocket was in flight. (Liquid oxygen, or LOX, is a commonly used as an oxidizer or propellant for rockets.) The leak led to what SpaceX CEO Elon Musk described at one point as an “RUD” — or “rapid unscheduled disassembly,” a phrase the company typically uses to refer to an explosion.
Within about two weeks of that explosion, the FAA determined there were “no public safety issues” involved and permitted SpaceX’s Falcon 9 to return to flight. Nevertheless, the FAA’s investigation into the mishap is still ongoing, the agency told CNN on Friday. That review is not related to the probe into the failed August 28 booster landing, meaning two investigations into separate Falcon 9 incidents are underway.
