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I know turbulence is a thing for aircraft etc. but I am not sure how even the dense clouds affect the flight path of a rocket?

I know the storm winds might affect the flight path of a rocket but if there are dense clouds and there are heavy winds how much they will effect the flight of rocket as it don't take much time to pass through the upper layers of the atmosphere?

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Thick clouds in general are not a trajectory issue but can pose a threat of rocket-triggered lightning. For STS flight rules were in place to mitigate the risk of lightning strikes (see table A2-6-III).

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Many rockets (for example Falcon 9) will have a Thick Cloud Rule as one of the launch constraints — if the density of height of a cloud exceeds a particular threshold, the launch will be postponed until the constraint is GO - making your question nonanswerable in some instances. Mission managers realize it can pose a danger so they will scrub. Here are the Falcon 9 weather commit criteria. These conditions are generally measured in the days and hours preceding a launch by the 45th Air Force Weather Squadron (at CCAFS).

Wind shear actually played a small part in the destruction of Space Shuttle Challenger in 1986 (although it was essentially doomed from the start):

...However, at around T+36 seconds and an altitude of just over 10,000 feet (3,000 m), Challenger experienced the strongest wind shear ever felt by a Space Shuttle launch. The pitch and yaw commanded by the shuttle's computers in order to counter this wind caused the solid fuel plug to become dislodged from the field joint on the right SRB...

Taken from the STS-51-L Mission Timeline.


In general terms, a rockets outcome can be expressed as a boolean: either the launch is a success and the payload reaches orbit, or the launch is not a success and the rocket will either explode, veer off trajectory (to be destroyed by range safety), or deliver a payload to a suboptimal orbit.

Considering that the most dangerous winds will be found when the vehicle isn't very high or very downrange, if the vehicle cannot self correct its trajectory to account for the wind shear or clouds by either throttling up slightly or gimballing its engines, it will veer outside its preplanned flight corridor, and as I mentioned, by automatically terminated by range safety.

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    $\begingroup$ ... unless the launch vehicles are ICBM derived. If they only worked in good weather, they would not be good weapons. $\endgroup$ – Rikki-Tikki-Tavi Jan 16 '15 at 2:25
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Usually, the rocket trajectory would be pre-planned on the ground to effectively point into the (expected) wind somewhat to reduce the angle-of-attack caused by the winds. Some rockets adjust their planned trajectory the day of launch to take into account the expected winds over a shorter duration.

If the trajectory was shaped for no wind, and day-of-launch you have the jet stream running overhead instead, I recall the difference might be up to 75 m/s of wind. Some rockets were designed with adaptive systems to adjust the pre-launch designed attitude profile into the wind based on in flight estimates of angle of attack, to reduce the angle attack effect of both the winds and sudden gusts on top of that, and perhaps even the effect of having lost one engine. But, having done so is a severe change to the trajectory for the rest of the flight after that so you have to have a fairly strong rocket (to survive the gusts) and extra propellant margin available to use to correct the trajectory after you fly through the maximum dynamic pressure area where the angle of attack limit is severe. All this is expensive to the payload capability of the rocket.

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