Is there a wind speed at which rocket landing is impossible or extremely risky?
[quote author=El Commediante For SpaceX at present, just demonstrating reusability is a coup; It seems it's possible to land a stage without this control authority, in the winds present on good-weather days. It's only when they're using landing regularly for frequent launches, and especially when Falcon Heavy is landing stages in two locations at once, that edge conditions like wind become bottlenecks on fleet function.
I believe the landing wind limited for the orbcomm flight was 50mph.Unlike launch, there's no nearby launch tower or lightning protection to be blown into.
Quote from: Burninate on 12/28/2015 12:13 am[quote author=El Commediante For SpaceX at present, just demonstrating reusability is a coup; It seems it's possible to land a stage without this control authority, in the winds present on good-weather days. It's only when they're using landing regularly for frequent launches, and especially when Falcon Heavy is landing stages in two locations at once, that edge conditions like wind become bottlenecks on fleet function.I would assume that landing weather limits are not that different from launch weather limits, so In the case of RTLS the bottleneck won't be as significant as you think.
Quote from: cscott on 12/29/2015 04:43 pmI believe the landing wind limited for the orbcomm flight was 50mph.Unlike launch, there's no nearby launch tower or lightning protection to be blown into.What's the launch wind criteria ?50mph (44 knots / 81 km/h) is a LOT of wind. Ultra rare having even 40 mph winds.Even for ASDS 44 knot wind is a substantial margin.
Quote from: macpacheco on 12/30/2015 07:22 amWhat's the launch wind criteria ?50mph (44 knots / 81 km/h) is a LOT of wind. Ultra rare having even 40 mph winds.Even for ASDS 44 knot wind is a substantial margin.Launch: <20Landing: <50I've asked Chris if he could verify the landing number (we need gust limit as well).That 50mph seems huge in terms of landing controlabity... If true, very impressive... IMO.
What's the launch wind criteria ?50mph (44 knots / 81 km/h) is a LOT of wind. Ultra rare having even 40 mph winds.Even for ASDS 44 knot wind is a substantial margin.
The stage isn't an airfoil. In fact its the opposite. A round shape does the best job of allowing the wind to flow around the object while generating as little reaction force to wind flow as possible.
Quote from: macpacheco on 12/30/2015 11:19 pmThe stage isn't an airfoil. In fact its the opposite. A round shape does the best job of allowing the wind to flow around the object while generating as little reaction force to wind flow as possible.Not much could be further from the truth.A cylinder like that has a drag coefficient of around 1.2!
Quote from: Lee Jay on 12/30/2015 11:21 pmQuote from: macpacheco on 12/30/2015 11:19 pmThe stage isn't an airfoil. In fact its the opposite. A round shape does the best job of allowing the wind to flow around the object while generating as little reaction force to wind flow as possible.Not much could be further from the truth.A cylinder like that has a drag coefficient of around 1.2!What better shape could be used ?
Quote from: macpacheco on 12/30/2015 11:19 pmThe stage isn't an airfoil. In fact its the opposite. A round shape does the best job of allowing the wind to flow around the object while generating as little reaction force to wind flow as possible.Not much could be further from the truth.A cylinder like that has a drag coefficient of around 1.2!Ever seen this drawing? This is to scale and both have about the same drag.
Quote from: Lee Jay on 12/30/2015 11:21 pmQuote from: macpacheco on 12/30/2015 11:19 pmThe stage isn't an airfoil. In fact its the opposite. A round shape does the best job of allowing the wind to flow around the object while generating as little reaction force to wind flow as possible.Not much could be further from the truth.A cylinder like that has a drag coefficient of around 1.2!Ever seen this drawing? This is to scale and both have about the same drag.That's only true for the wind direction indicated. If the wind was 90 degrees to that, the results would be different! Real winds come from all directions and a cylinder is symmetric.