ASAP member Don McErlean outlined several issues that SpaceX’s Crew Dragon spacecraft needs to overcome, including a lack of a final resolution on the root cause of the failure of a composite overwrapped pressure vessel (COPV) that led to the pad explosion of a Falcon 9 more than two years ago. That is linked, he added, to the use of “load-and-go” fueling of the rocket that would take place, on commercial crew missions, after astronauts have boarded the spacecraft.
The use of additive manufacturing is a key element in Aerojet’s updated version of the engine, the RL10C-X, intended to lower its cost without compromising reliability or performance. 0806名無しさん＠お腹いっぱい。2018/10/18(木) 00:59:33.10ID:8U9gnOEZ>>804 マーク 0807名無しさん＠お腹いっぱい。2018/10/18(木) 01:22:21.62ID:kw6JCZI+>>804 得意技とか意味の分からないことを喚かれても困るんだが… 大方お前が自分に批判的なのは同一人物だと勝手に思い込んでるだけだろうが
＞Will the BFS PICA-X heat shield be mounted on top of a common, ＞single piece of 9m diameter cylindrical carbon-fiber outer tank skin additively, ＞or will it be an integrated part of the outer BFS skin?
＞Elon Musk (Official) ＞The heat shield plates will be mounted directly to the primary tank wall. ＞That's the most mass efficient way to go. Don't want to build a box in box.
＞so lowest mass solution is just to mount the heat shield plates directly to the tank wall.
＞For the Dragon’s heat shield, the company chose a material called PICA ＞(phenolic impregnated carbon ablator), first developed for NASA’s Stardust ＞comet-sample-return spacecraft. ＞Rejecting the prices they were getting from the manufacturer, they took advantage of ＞help from NASA’s Ames Research Center to make it themselves. ＞According to Mueller, SpaceX’s material, called PICA-X, is 10 times less expensive than the original, ＞“and the stuff we made actually was better.” ＞In fact, says Musk, a single PICA-X heat shield could withstand hundreds of returns from low Earth orbit; ＞it can also handle the much higher energy reentries from the moon or Mars.
5. 超音速による未知のダメージ 0861名無しさん＠お腹いっぱい。2018/10/21(日) 02:54:11.66ID:nLbMohec >Merlin 1D Falcon 9 v1.1 Topic: SpaceX Falcon 9 v1.1 DISCUSSION AND UPDATES (THREAD 5) http://forum.nasaspaceflight.com/index.php?topic=33335.msg1125118#msg1125118 we're only actually operating the engines at about 85% of their potential, so ah, down the road, future missions, we anticipate being able to crank them up to their full thrust capability of, uh, which would give about 165000 pounds of sea level thrust per engine. 0862名無しさん＠お腹いっぱい。2018/10/21(日) 13:41:12.93ID:cvAFbsmh リフティングボディも水平着陸なら自然な帰結だけど、 垂直着陸かつ打ち上げ単価安いBFRの場合、軌道上で燃料再補給して、逆噴射で減速した方が現実的だったりして。 0863名無しさん＠お腹いっぱい。2018/10/21(日) 14:30:42.59ID:07YzKfWhhttps://rio2016.5ch.net/test/read.cgi/galileo/1537599679/624 >Σmv=一定 >に時間の変数は含まれない。
