What are the best weather conditions for manned space launches?

The best meteorological conditions for manned space launches mainly include: total cloud cover 0-30%, no precipitation; ground wind speed less than 8 meters/second; horizontal visibility greater than 20 kilometers; 8 hours before launch to launch One hour later, there was no lightning activity within 30 kilometers to 40 kilometers of the site; the maximum wind speed at an altitude of 3 kilometers to 18 kilometers through the airspace where the ship and arrow was launched was less than 70 meters per second.

The most important weather factor during launch is the high-altitude wind 8-15 kilometers above the ground. Liu Hantao said that this is the place with the highest wind speed in the atmosphere. Too much wind speed will affect the attitude of the rocket. At the same time, if the wind shear is too large, for example, the wind speed is different between the upper and lower levels, or the direction of the wind is different, it may cause the rocket to distort.

Other factors that affect emission include cloud cover, visibility, precipitation, ground atmospheric electric field strength, etc.

Extended information

Weather has the greatest impact on the two aspects of manned space launch: transfer and launch.

Transfer refers to the transfer of the 58.3-meter-high ship and arrow assembly from the assembly plant to the launch tower, with a distance of 1,500 meters. This is also the stage when the ship and arrow are exposed to the outdoors for the longest time.

Liu Hantao said that the biggest impact at this time is the shallow wind below 80 meters above the ground. Because the spacecraft has been refueled during the transfer, the rocket has not been refueled, and it is in a top-heavy state. Excessive wind speed may cause The rocket loses its balance.

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