Unfavourable weather conditions forced NASA and SpaceX to call off the first crewed flight from US soil in nearly a decade yesterday.

American astronauts Doug Hurley and Bob Behnken were due to liftoff from Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 4.33pm EDT, but bad weather forced mission managers to pull the plug just 16 minutes before launch.

“I know there’s a lot of disappointment today. The weather got us,” NASA Administrator Jim Bridenstine said. “But it was a great day for NASA. It was a great day for SpaceX. Our teams worked together in a really impressive way, making good decisions all along.”

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Source: NASA/Joel Kowsky

NASA said the countdown proceeded smoothly throughout the day yesterday, with no technical issues raised regarding the SpaceX Falcon 9 rocket or the Crew Dragon spacecraft.

But later in the day with operations underway to load the rocket’s propellants and the instantaneous launch window of 4:33 p.m. EDT drawing near, launch weather officials briefed SpaceX Launch Director Mike Taylor that there just wasn’t enough time to wait for weather to improve.

Rain, cumulus clouds, attached anvil clouds, lightning and field mill data – which measure the amount of electricity in the atmosphere – all violated Falcon 9 and Crew Dragon launch criteria at times throughout the day.

“There was a concern that if we did launch, it could actually trigger lightning,” Bridenstine said. “We made the right decision.”

The Demo-2 mission, dubbed Launch America, has been postponed until 3.22pm EDT on Saturday (30th May).