Stage 1's don't spend enough time in the upper atmosphere to get much benefit from a ballute. They are coming back down into the denser atmosphere before the ballute could slow it down much.
Will you still be able to fine tune trajectory while a ballute is in use? Or in a passive sense, how much change in trajectory can be expected?
Someone also proposed sending up a weather balloon to get accurate information on wind patterns, so you can correct using the landing ship instead of the craft.
Shuttlecock style with the ballute cone poking out of the top in a trailing configuration means your engine is fully exposed though.
Uh, not so obvious is, is this a top first or bottom first HIAD style ballute, of something like a shuttlecock with the engines first?From a weight perspective being engine down is easier.Shuttlecock style with the ballute cone poking out of the top in a trailing configuration means your engine is fully exposed though. ...
A 100x increase in BC means a ballute about 30 m in diameter. A 30 m spherical Kapton balloon of 4 mil thickness would mass 322 kg and could hold 26 kg of He at 25 C and 1 kPa (about the air pressure at 30 km). Kapton is usable up to about 400 C.
Quote from: envy887 on 04/20/2018 02:32 pmA 100x increase in BC means a ballute about 30 m in diameter. A 30 m spherical Kapton balloon of 4 mil thickness would mass 322 kg and could hold 26 kg of He at 25 C and 1 kPa (about the air pressure at 30 km). Kapton is usable up to about 400 C. Or more like 50m^2 if considering it going in 'belly first'.I do wonder when we'll first see hardware.
Quote from: speedevil on 04/20/2018 03:36 pmQuote from: envy887 on 04/20/2018 02:32 pmA 100x increase in BC means a ballute about 30 m in diameter. A 30 m spherical Kapton balloon of 4 mil thickness would mass 322 kg and could hold 26 kg of He at 25 C and 1 kPa (about the air pressure at 30 km). Kapton is usable up to about 400 C. Or more like 50m^2 if considering it going in 'belly first'.I do wonder when we'll first see hardware.If coming in belly first, why not face the incoming side with BFS thermal protection (and winglets?) allowing them to test those? Use a small ballute(s) to keep it oriented.