SpaceX aborted a Falcon 9 launch attempt Thursday less than a minute before liftoff from Vandenberg Space Force Base in California, the company’s first terminal countdown interruption in more than 18 months for reasons other than bad weather or range safety.
The Falcon 9 rocket was scheduled to lift off on SpaceX’s Starlink 3-2 mission at 10:39 a.m. PDT (1:39 p.m. EDT; 1739 GMT) Thursday from a foggy launch pad at Vandenberg, a military spaceport about 145 miles (225 kilometers) away. ) northwest of Los Angeles.
But the countdown data sequences interrupted the pre-launch sequence at T-minus 46 seconds. SpaceX did not identify a reason for the delay, but weather parameters and the military range at Vandenberg were “go” for launch.
The company had two immediate launch opportunities Thursday to line up orbital planes in the company’s Starlink internet constellation. There are 46 Starlink internet satellites awaiting launch from California on the Falcon 9 rocket.
The options for SpaceX’s launch team are also limited when the Falcon 9 rocket is loaded with propellants. The Falcon 9 uses condensed, supercooled kerosene and liquid oxygen propellants, and the liquids can get too hot if the rocket stays on the ground too long before liftoff.
SpaceX’s launch director announced Thursday that the countdown was scrubbed, and teams began preparations to drain propellant from the two-stage Falcon 9 rocket. Officials tentatively set another launch attempt for Friday at the same time — 10:39 a.m. PDT.
The last time a technical issue forced SpaceX to halt a countdown in the final phase of countdown preparations was in December 2020 at a launch from Florida for the National Reconnaissance Office. During that launch attempt, SpaceX engineers identified an unexpected pressure reading in the Falcon 9’s upper stage liquid oxygen tank, lowered the rocket horizontally for troubleshooting, then launched the mission two days later.
SpaceX has scrubbed several Falcon 9 countdowns since December 2020 due to bad weather or range violations from ships or aircraft that ventured into restricted airspace or waters near the launch site. And there have been a few launch delays caused by concerns with the Falcon 9 rocket or ground systems, but none of these occurred in the final countdown sequence before launch.
SpaceX has launched 62 Falcon 9 rocket missions since the NROL-108 launch was scrubbed by a technical problem more than 18 months ago.
The launch of the next 46 Starlink satellites from California will mark the 32nd flight of a Falcon 9 rocket this year, breaking the record of 31 missions in a calendar year set in 2021.
And the year is barely halfway over, meaning SpaceX is on pace to nearly double the number of launches it completed in 2021. SpaceX has launched more successful missions into orbit so far this year than the combined efforts of any other nation, and the company is far surpassing the main competitors on the commercial market.
United Launch Alliance, a rival in the competition for US military launch operations, has launched four times this year. Arianespace, the European commercial launch company, has carried out three missions so far in 2021.
SpaceX said the first 31 missions of the year delivered about 351 tons (about 774,000 pounds) of payload mass into orbit. The flights have carried astronauts to the International Space Station, launched hundreds of small satellites for the Starlink network and customer fleets, and deployed national security payloads for the US government’s spy satellite agency.
As SpaceX prepares for the launch of the Starlink 3-2 mission, workers at the Kennedy Space Center are preparing another Falcon 9 rocket for launch from pad 39A as early as Sunday with another group of Starlink Internet satellites.
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