<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:14pt"><div><span>Spike wrote:</span></div><div><span></span> </div><div><span>> Agreed, but my own favorite idea for a payload is only a few tens of grams.</span></div><div><span></span> </div><div><span><a href="http://tech.groups.yahoo.com/group/Ice_Station/message/473">http://tech.groups.yahoo.com/group/Ice_Station/message/473</a></span></div><div><span></span> </div><div><span>This is a link in the discussion of using E&M coilguns to</span></div><div><span>launch what I called Needle-Satellites from high altitude</span></div><div><span>aircraft. Something for the tens of grams launches Spike</span></div><div><span>is interested in.</span></div><div><span><var id="yui-ie-cursor"></var></span> </div><div><span>Dennis May</span></div><div><br></div><div style="font-family: times new roman, new york,
times, serif; font-size: 14pt;"><div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"><font size="2" face="Arial"><div style="margin: 5px 0px; padding: 0px; border: 1px solid rgb(204, 204, 204); height: 0px; line-height: 0; font-size: 0px;" class="hr" contentEditable="false" readonly="true"></div><b><span style="font-weight: bold;">From:</span></b> spike <spike66@att.net><br><b><span style="font-weight: bold;">To:</span></b> 'ExI chat list' <extropy-chat@lists.extropy.org><br><b><span style="font-weight: bold;">Sent:</span></b> Tuesday, November 8, 2011 7:03 AM<br><b><span style="font-weight: bold;">Subject:</span></b> Re: [ExI] Launching Satellites from Airplanes DARPA<br></font><br>
>... On Behalf Of Eugen Leitl<br>Subject: Re: [ExI] Launching Satellites from Airplanes DARPA<br><br>On Mon, Nov 07, 2011 at 06:20:54PM -0800, spike wrote:<br><br>>> My own experience with it is that the problem doesn't scale down very<br>well.<br>> Every design I have derived has the cost per kg to LEO increasing <br>> dramatically once the total payload goes much below 1000 kg. I am <br>> cheering wildly for anyone who can get those costs down.<br><br>>...A ton to LEO can go a long way.<br><a href="https://secure.wikimedia.org/wikipedia/en/wiki/SMART-1" target="_blank">https://secure.wikimedia.org/wikipedia/en/wiki/SMART-1</a><br><br>Agreed, but my own favorite idea for a payload is only a few tens of grams.<br><br><br>My best efforts at a very small rocket yielded a puzzling outcome: once you<br>get much below about a ton, the rocket mass and cost don't go down much<br>more. It takes about the same rocket to hoist 1 kg
as it takes to hoist<br>100. At some point, the flight controls problem doesn't scale down, rather<br>it starts to scale up. Smaller rockets take more computing power to keep<br>them flying pointy-end-first: the feedback loop needs to be faster.<br><br>spike <br><br><br><br><br>_______________________________________________<br>extropy-chat mailing list<br><a href="mailto:extropy-chat@lists.extropy.org" ymailto="mailto:extropy-chat@lists.extropy.org">extropy-chat@lists.extropy.org</a><br>http://lists.extropy.org/mailman/listinfo.cgi/extropy-chat<br><br><br></div></div></div></body></html>