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I get that you dont want to fly a giant rocket full of liquid oxygen and other explosives into a thunderstorm or hurricane, but what are some practical reasons

by S_A_P 6y ago

I get that you dont want to fly a giant rocket full of liquid oxygen and other explosives into a thunderstorm or hurricane, but what are some practical reasons for postponing a launch due to weather. As I (hardly) understand once you get high up in the atmosphere there is high wind even on a clear day, does rain matter that much?

greedo 6y ago
The weather needs to be good enough for a safe recovery downrange if there's an abort.
ceejayoz 6y ago
Various reasons, well explained here (in several answers, including one pointing out that Challenger blew up in part due to cold weather): https://space.stackexchange.com/questions/4967/why-are-rocket-launches-so-sensitive-to-weather https://space.stackexchange.com/questions/4967/why-are-rocke...
danbr 6y ago
I would think by far it’s for crew safety. Recovery due to an in-flight abort would be difficult in rough seas and weather if they had to be plucked out of the Atlantic. The aerostructure of the falcon 9 can only withstand so much side loading due to aerodynamic forces and wind before exceeding the operational limits of the rocket (body to keep it all from breaking apart, and the engines working hard to keep them on the correct trajectory).
- S_A_P 6y ago
  Thank you for the answer. To those who downvoted- I normally don't comment on that, but damn it was an honest question and I admitted to having little knowledge on this and its not like I gave a hot take. Just wanting to learn something...
ncallaway 6y ago
First of all, weather is much more than just rain. One of the things that's monitored closely in the launch corridor are the upper atmospheric winds. Specifically the wind sheer in the upper atmosphere. Strong wind isn't typically a problem, but high wind sheer in the upper atmosphere can be problematic. Additionally, they check the weather in the entire recovery corridor. That is, anywhere that the capsule could end up during an abort. They want to make sure that if the capsule ends up in the ocean, the weather permits recovery operations. An abort and safe splash-down doesn't do us much good if the astronauts then drown because recovery operations are impaired due to weather. We're putting two lives on this rocket. A small delay is absolutely the right trade-off to reduce risk.
mlindner 6y ago
The issue isn't so much high wind but wind shear. Namely when you pass through a sharp change in air direction there's a bending force applied to the rocket that's proportional to the vehicle speed and atmospheric density. This can get very high and risk destroying the rocket.

by S_A_P 6y ago

greedo 6y ago

The weather needs to be good enough for a safe recovery downrange if there's an abort.

ceejayoz 6y ago

Various reasons, well explained here (in several answers, including one pointing out that Challenger blew up in part due to cold weather): https://space.stackexchange.com/questions/4967/why-are-rocket-launches-so-sensitive-to-weather https://space.stackexchange.com/questions/4967/why-are-rocke...

danbr 6y ago

I would think by far it’s for crew safety. Recovery due to an in-flight abort would be difficult in rough seas and weather if they had to be plucked out of the Atlantic. The aerostructure of the falcon 9 can only withstand so much side loading due to aerodynamic forces and wind before exceeding the operational limits of the rocket (body to keep it all from breaking apart, and the engines working hard to keep them on the correct trajectory).

S_A_P 6y ago
Thank you for the answer. To those who downvoted- I normally don't comment on that, but damn it was an honest question and I admitted to having little knowledge on this and its not like I gave a hot take. Just wanting to learn something...

ncallaway 6y ago

First of all, weather is much more than just rain. One of the things that's monitored closely in the launch corridor are the upper atmospheric winds. Specifically the wind sheer in the upper atmosphere. Strong wind isn't typically a problem, but high wind sheer in the upper atmosphere can be problematic. Additionally, they check the weather in the entire recovery corridor. That is, anywhere that the capsule could end up during an abort. They want to make sure that if the capsule ends up in the ocean, the weather permits recovery operations. An abort and safe splash-down doesn't do us much good if the astronauts then drown because recovery operations are impaired due to weather. We're putting two lives on this rocket. A small delay is absolutely the right trade-off to reduce risk.

mlindner 6y ago

The issue isn't so much high wind but wind shear. Namely when you pass through a sharp change in air direction there's a bending force applied to the rocket that's proportional to the vehicle speed and atmospheric density. This can get very high and risk destroying the rocket.