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> What was SFO going to do if it clouded over, close the airport?

No, land planes at a slower rate (about half) because they can no longer land two planes side by side on the parallel runways. On a day when the weather is known to be cloudy and that is factored in up front, that's not a huge problem.

On a day when the weather is clear and planes are landing at the higher rate, it is a huge problem.

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> On a day when the weather is known to be cloudy and that is factored in up front, that's not a huge problem.

> On a day when the weather is clear and planes are landing at the higher rate, it is a huge problem.

But it can get cloudy any time in SF. So suddenly needing to switch over to ILS operations should be something they're set up to handle pretty routinely.

They would normally have warning from weather forecasters about upcoming cloudy weather so they would have time to switch over to ILS operations in an orderly manner. Switching in the middle of a clear evening because of one plane is something quite different.

again, the ILS wasn't unavailable, but ATC for hundreds of miles had been planning on every plane taking the visual, with its reduced separation requirements. if a plane needs an approach with increased requirements, they need to tell ATC early so ATC can put them in their plan.

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