Imma Perfetto
Cosmos science journalist
SpaceX’s Falcon 9 has been cleared to return to flight following the rare failure on July 11, which resulted in all 20 Starlink satellites from the launch re-entering the Earth’s atmosphere and burning up.
Following SpaceX’s public safety determination request on July 15, the US Federal Aviation Administration (FAA) gave approval for the Falcon 9 to return to flight on July 25.
According to SpaceX, Falcon 9 could liftoff with 23 Starlink satellites as soon as tomorrow Saturday 27 July.
“The FAA is responsible for and committed to protecting the public during commercial space transportation launch and reentry operations,” the FAA said in a statement to Cosmos.
“After a comprehensive review, the FAA determined no public safety issues were involved in the anomaly that occurred during the SpaceX Starlink Group 9-3 launch on July 11.
“This public safety determination means the Falcon 9 vehicle may return to flight operations while the overall investigation remains open, provided all other license requirements are met.”
According to a July 25 update, SpaceX submitted its mishap report to the FAA. The most probable cause of the mishap and the corrective actions needed to ensure the success of future missions have been identified.
“Post-flight data reviews confirmed … during the first burn of Falcon 9’s second stage engine, a liquid oxygen leak developed within the insulation around the upper stage engine,” SpaceX said.
“The cause of the leak was identified as a crack in a sense line for a pressure sensor attached to the vehicle’s oxygen system. This line cracked due to fatigue caused by high loading from engine vibration and looseness in the clamp that normally constrains the line.
“A second burn of the upper stage engine was planned to circularise the orbit ahead of satellite deployment. However, the liquid oxygen leak on the upper stage led to the excessive cooling of engine components, most importantly those associated with delivery of ignition fluid to the engine. As a result, the engine experienced a hard start rather than a controlled burn, which damaged the engine hardware and caused the upper stage to subsequently lose attitude control.”
SpaceX says the failed sense line and sensor on the second stage engine will be removed for near term Falcon launches.
“The sensor is not used by the flight safety system and can be covered by alternate sensors already present on the engine. The design change has been tested at SpaceX’s rocket development facility in McGregor, Texas, with enhanced qualification analysis and oversight by the FAA and involvement from the SpaceX investigation team.”
SpaceX is now targeting Saturday, July 27 for a Falcon 9 launch of 23 Starlink satellites to low-Earth orbit from Launch Complex 39A (LC-39A) at NASA’s Kennedy Space Center in Florida.
“Liftoff is targeted for 12:21 am ET, with backup opportunities available until 4:21 am ET. If needed, additional opportunities are also available on Sunday, July 28 starting at the same time.
“A live webcast of this mission will begin about five minutes prior to liftoff, which you can watch here and on X @SpaceX.”
