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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This caught my attention because I have long thought of this approach as compelling:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="http://cosmiclog.msnbc.msn.com/_news/2011/04/04/6409132-spacex-shoots-for-next-big-thing">http://cosmiclog.msnbc.msn.com/_news/2011/04/04/6409132-spacex-shoots-for-next-big-thing</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It has advantages in structural dynamics to have side-by-side boosters instead of stacked vertically. The aerodynamic disadvantage of that arrangement is more than compensated by weight savings in structural rigidity. It has costs in replicating the thrust vector control so many times, and it has disadvantages in reliability, since the risk of failure in one or more of the 27 nozzles, but the design can likely tolerate any one failing, and some pairs, so long as they are not adjacent.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>spike<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>