A SpaceX Falcon 9 rocket launched from Cape Canaveral Space Force Station on Wednesday, August 28.
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SpaceX’s prolific Falcon 9 rocket has been grounded for the second time in two months after federal regulators said they wanted to review a wayward landing attempt that occurred Wednesday morning.
That makes the Falcon 9 rocket unable to fly with two key human spaceflight missions on the horizon.
The company is slated to launch a daring mission called Polaris Dawn as soon as this week, and next month it’s expected to launch two NASA astronauts to the International Space Station on Crew-9, a mission that — after a months-long rotation — will also bring home Boeing Starliner’s test flight crew. NASA astronauts Suni Williams and Butch Wilmore have been in limbo on the orbiting laboratory since their Starliner flight in early June.
Wednesday’s incident involved the first stage of a Falcon 9 rocket — or the bottommost portion that gives the first burst of power at liftoff — which failed to land upright on a seafaring platform and exploded. The overall mission, however, appeared to go off without a hitch, safely delivering a batch of SpaceX’s Starlink internet satellites into orbit.
Still, the Federal Aviation Administration, which licenses commercial rocket launches, said it would investigate the mishap.
“The FAA is aware an anomaly occurred during the SpaceX Starlink Group 8-6 mission that launched from Cape Canaveral Space Force Station in Florida on August 28,” the FAA said Wednesday in a statement. “The incident involved the failure of the Falcon 9 booster rocket while landing on a droneship at sea. No public injuries or public property damage have been reported. The FAA is requiring an investigation.”
Landing the first-stage booster is a signature SpaceX move. Other rockets flying today typically discard their first stage boosters after flight. SpaceX, however, aims to recover and refurbish its Falcon 9 boosters as often as possible to save money.
SpaceX does not typically experience delays or lengthy groundings after losing a booster, as the loss does not affect the success of the primary mission.
Wednesday’s announcement, however, could complicate SpaceX’s plans to get Polaris Dawn off the ground. That mission, carrying a four-person crew, was set to take off early this morning, but was delayed because of weather forecasts. The company would have been able to try again as soon as Friday.
It’snot clear how long the Falcon 9 will remain grounded. After the mishap in July, the rocket was taken out of flight for a couple of weeks.
A prior anomaly
Unlike Wednesday’s mishap, the July Falcon 9 failure involved the rocket’s second stage.
A Falcon 9 had launched a group of Starlink satellites out of California on July 11 shortly before the anomaly occurred.
The first leg of the mission appeared to proceed smoothly, with the Falcon 9 using its first-stage booster — the bottommost part of the rocket with nine engines that provide the initial burst of power at liftoff — to propel itself toward space.
But the second stage of the rocket, which is designed to fire up after the first stage falls away and power the satellites to their final destination in orbit, failed abruptly.
SpaceX later revealed there was an oxygen leak on that second stage. (Liquid oxygen or LOX is a commonly used as an oxidizer or propellant for rockets.) That led to what SpaceX CEO Elon Musk described at one point as an “RUD” — or “rapid unscheduled disassembly,” a phrase SpaceX typically uses to refer to an explosion.
Within about two weeks of that incident, the FAA had determined there were “no public safety issues” involved and permitted SpaceX’s Falcon 9 to return to flight,though an investigation into the mishap overseen by the FAA is still ongoing, the agency confirmed to CNN on Wednesday. That review is not related to the investigation into the latest anomaly.
The company had determined the leak was caused by a crack in a line attached to a pressure sensor, which endured some wear and tear from engine vibrations and the fact that a clamp that was meant to strap it down had come loose. The oxygen leak caused “excessive cooling” of engine parts, which left the rocket without enough fuel to burn properly, said Sarah Walker, SpaceX’s director of Dragon mission management, during a July 26 news briefing.
The company opted to implement a temporary fix for the issue by simply removing the pressure sensor at issue and relying on data from other instruments.
On Wednesday, SpaceX confirmed that its latest Starlink flight did not experience any issues with its second stage, writing that a regular “orbit (was) achieved by Falcon 9’s upper stage after its second burn.”
But the company also added that it would forgo an attempt to launch a second Starlink mission overnight in order to allow its engineers to investigate why the first-stage booster did not land correctly.
“Standing down from our second @Starlink launch of the night to give the team time to review booster landing data from the previous launch,” according to a post from SpaceX on X. “A new target launch date will be shared once available.”
