tag:blogger.com,1999:blog-7598615455712402973.post6808647134196751401..comments2024-03-29T08:20:04.423-04:00Comments on Polymath: A liquid-fueled Indian manned launcher. UPDATED.Robert Clarkhttp://www.blogger.com/profile/16114043697010364282noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-7598615455712402973.post-79945859855895982762015-01-02T10:39:27.405-05:002015-01-02T10:39:27.405-05:00Large solids also suffer from vibration problems. ...Large solids also suffer from vibration problems. These were mitigated on the space shuttle by the presence of the ET between the SRBs and the orbiter. However, the inline design of Ares I proved to be troublesome due to vibration issues.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7598615455712402973.post-6658968817592614252014-12-28T18:24:29.525-05:002014-12-28T18:24:29.525-05:00There are basically two (credible) failure modes w...There are basically two (credible) failure modes with solids as boosters (when designed and tested properly). (1) Seals can leak as in the Challenger disaster. (2) voids or cracks in the propellant cause overpressure-burst disasters. The third issue is poor motor design from a fundamentals standpoint, root of the AFRPL thrust stand explosion that caused a billion-dollar write-off for what was Hercules Aerospace in the 1990's. <br /><br />Item (1) is a seal-and-joint design problem. Item (2) is a processing quality control problem. Simple as that, and just as complex, too. Solve those and there is no reason you cannot use solids in a manned system. They can be solved, but the solutions are unknown to government labs. Not all contractors can do these "right" either. Some cannot even do that third egregious item correctly. The SLS SRB instability is one of those. <br /><br />GW<br /><br />Gary Johnsonhttps://www.blogger.com/profile/06723964751681093047noreply@blogger.com