<font face="arial" size="3"><p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">There are a couple of members interested in hybrid motors.. Thought I think we've finally got enough people interested in APC mixing that we seen to be inching more in that direction currently. Although there is some cool new stuff also happening in the hybrid motor space. With the addition of additive manufacturing (3D printed plastic fuel grains), they're able to make hybrid grains that were previously impossible:</p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"><a href="https://en.wikipedia.org/wiki/Hybrid-propellant_rocket#Additive_manufacturing">https://en.wikipedia.org/wiki/Hybrid-propellant_rocket#Additive_manufacturing</a></p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">That being said.. I've been to a couple of hybrid only launches back in the day when I lived in Texas. It <em>IS</em> a lot of ground support.. too much if you ask me. Handling bottles of oxygen and nitrous make me a little nervous too (there's a lot that can wrong). Here's some pics of Art Applewhite and I helping oversee a NASA sponsored launch just north of San Antonio back in 2007 that NASA and the state of Texas threw a lot of money at. </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"><a href="http://theweeks.org/rockets/2007-04_LAUNCH/">http://theweeks.org/rockets/2007-04_LAUNCH/</a></p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">Most rockets flown that day were around $2k each.. and none of them had a successful recovery. I've never seen so much wasted hardware at one event.. all while the parents and teachers clapped and cheered.. it was like a dang fireworks show.</p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">All that to say.. I don't have happy memories of watching people fly overpriced hybrid setups.. But as a rocket lover.. the technology is still pretty cool.. even though I still suffer flashbacks.. ;)</p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">Tweeks</p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;">On Monday, October 22, 2018 10:16am, "Adrien Drouault" <adrien.drouault@gmail.com> said:<br /><br /></p>
<div id="SafeStyles1540266038">
<div>Yep; I took my test last weekend, and the study guide is still dated 2012.
<div>As for hybrids, I'd love to work with one at some point, but with all the GSE, it's definitely an undertaking.</div>
</div>
<br />
<div class="gmail_quote">
<div dir="ltr">On Mon, Oct 22, 2018, 10:07 Weeks, Thomas <<a href="mailto:t.weeks@vt.edu">t.weeks@vt.edu</a>> wrote:</div>
<blockquote class="gmail_quote" style="margin: 0 0 0 .8ex; border-left: 1px #ccc solid; padding-left: 1ex;">
<div>
<div class="m_-3459826233514180677moz-cite-prefix">On 10/22/2018 12:53 AM, Jim Stoll wrote:</div>
<blockquote>
<div class="m_-3459826233514180677ydp214bc684yahoo-style-wrap" style="font-family: Helvetica Neue,Helvetica,Arial,sans-serif; font-size: 16px;">
<div>PS - what is the obsession w/ Hybrid rocket motor questions? Over 10% of the technical question pool is about hybrid rocket motors, yet I can't find any hybrid motors for sale anywhere...???</div>
</div>
</blockquote>
<br /> Yeah.. back when the ATFE was trying to regulate HP/APC motors, a lot of people were looking into transitioning from APC to hybrid to preserve the hobby. However, the cost and complexity of HPC, and then eventual winning of the case with the ATFE brought a solid resurgence to the APC side fo the hobby, and Hybrid has since become less popular. It's still interesting stuff I think most certified fliers should at least know of.. but if you ask Bob, I bet and answer to YOUR question is just that the TRA has not updated the cert questions in a while. I know the last time I took it there were some out of date/incorrectly worded questions still in the pool.<br /><br /><br /> Bob?<br /><br /> Tweeks<br /><br />
<blockquote>
<div class="m_-3459826233514180677ydp214bc684yahoo-style-wrap" style="font-family: Helvetica Neue,Helvetica,Arial,sans-serif; font-size: 16px;"></div>
<div id="m_-3459826233514180677ydp7c44a4f2yahoo_quoted_0963466505" class="m_-3459826233514180677ydp7c44a4f2yahoo_quoted">
<div style="font-family: 'Helvetica Neue',Helvetica,Arial,sans-serif; font-size: 13px; color: #26282a;">
<div>On Monday, October 22, 2018, 12:10:04 AM EDT, Thomas Tweeks Weeks <a class="m_-3459826233514180677moz-txt-link-rfc2396E" rel="noreferrer" href="mailto:tom@theweeks.org" target="_blank"> <tom@theweeks.org></a> wrote:</div>
<div>
<div id="m_-3459826233514180677ydp7c44a4f2yiv7790113869">
<div>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">Thanks for bringing up these two great references Adrien.. I too would recommend them to anyone wanting to go a bit deeper into the hobby.</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">I've got both books.. and each is very different in how to covers HPR, but still good books to check out.</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">The <span style="color: #000000; font-family: arial; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; background-color: #ffffff; text-decoration-color: initial; display: inline; float: none;"><span> </span></span><a style="font-family: arial; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; background-color: #ffffff;" rel="nofollow noreferrer" href="https://smile.amazon.com/Modern-High-Power-Rocketry-Mark-Canepa/dp/1412058104/" target="_blank">Modern High Power Rocketry 2</a> book is awesome. It's old but contains a widely sourced plethora of best practices, tricks & tips, and wisdom harvested from many HPR communities and experts. It's a lot of info.. and is a little haphazard in its layout and flow, but still recommended as a great off-line resource and I still keep it by my build workbench. </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">I was glad to see<span style="color: #000000; font-family: arial; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; background-color: #ffffff; text-decoration-color: initial; display: inline; float: none;"><span> </span></span><a style="font-family: arial; font-size: 16px; font-style: normal; font-weight: 400; letter-spacing: normal; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; background-color: #ffffff;" rel="nofollow noreferrer" href="https://smile.amazon.com/Make-High-Power-Construction-Certification-Thousands/dp/1457182971/" target="_blank">Make: High Power Rockets</a> recently come on the scene as a newer publication. I like this book as it's a cleaner, simple read and more about a single person's journey fom the world of low power model rockets into HPR and certification than as much of a desktop reference like MHPR2. The author does scratch the surface of altimeters, pyrogens, recovery system design, and several other important HPR topics.. but it's just not nearly as deep as MHPR2 gets.</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">Recommend checking out both, if you can. Maybe I'll bring them in to our next meeting if we get some time in December.</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">Tweeks</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
<div id="m_-3459826233514180677ydp7c44a4f2yiv7790113869yqt77602" class="m_-3459826233514180677ydp7c44a4f2yiv7790113869yqt2570797925">
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;">On Sunday, October 21, 2018 12:00pm, "Adrien Drouault" <a class="m_-3459826233514180677moz-txt-link-rfc2396E" rel="noreferrer" href="mailto:adrien.drouault@gmail.com" target="_blank"> <adrien.drouault@gmail.com></a> said:<br /><br /></p>
<div id="m_-3459826233514180677ydp7c44a4f2yiv7790113869SafeStyles1540180158">
<div dir="ltr">If you like books, I would recommend <a rel="nofollow noreferrer" href="https://smile.amazon.com/Modern-High-Power-Rocketry-Mark-Canepa/dp/1412058104/" target="_blank"> Modern High Power Rocketry 2</a> (now 13 years old... Also, the formatting of the Nook version is kind of messed up), and <a rel="nofollow noreferrer" href="https://smile.amazon.com/Make-High-Power-Construction-Certification-Thousands/dp/1457182971/" target="_blank"> Make: High Power Rockets</a> (published late last year; I haven't noticed any formatting issues in the Kindle version).</div>
<br />
<div class="m_-3459826233514180677ydp7c44a4f2yiv7790113869gmail_quote">
<div dir="ltr">On Sun, Oct 21, 2018 at 11:05 AM <a rel="nofollow noreferrer" href="mailto:tweeks@theweeks.org" target="_blank"> tweeks@theweeks.org</a> <<a rel="nofollow noreferrer" href="mailto:tweeks-imap@theweeks.org" target="_blank">tweeks-imap@theweeks.org</a>> wrote:</div>
<blockquote class="m_-3459826233514180677ydp7c44a4f2yiv7790113869gmail_quote" style="margin: 0 0 0 .8ex; border-left: 1px #ccc solid; padding-left: 1ex;">
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Was just thinking, with our newer HP members and students might find these HP documents useful:</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Rocketry Glossary - <a rel="nofollow noreferrer" href="http://www.rocketmime.com/space/glossary.html" target="_blank"> http://www.rocketmime.com/space/glossary.html</a></p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">TRA Safety "SLP" Card - <a rel="nofollow noreferrer" href="http://server2.nrvr.org/files/2017_SLP-card.pdf" target="_blank"> http://server2.nrvr.org/files/2017_SLP-card.pdf</a></p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">TRA HP Safety Code - <a rel="nofollow noreferrer" href="http://server2.nrvr.org/files/2017_HighPowerSafetyCode.pdf" target="_blank"> http://server2.nrvr.org/files/2017_HighPowerSafetyCode.pdf</a></p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Getting Started w/High Power - <a rel="nofollow noreferrer" href="http://nrvr.org/what-is-high-power-rocketry/" target="_blank"> http://nrvr.org/what-is-high-power-rocketry/</a></p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Just off the top of my head..</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Anyone else have anything useful to share for newer folks/students?</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Tweeks</p>
<p style="margin:0;padding:0;margin: 0; padding: 0; font-family: arial; font-size: 12pt; word-wrap: break-word;" dir="ltr">Sent by <a rel="nofollow noreferrer" href="http://www.mail-wise.com/installation/2" target="_blank"> MailWise</a> – See your emails as clean, short chats.</p>
_______________________________________________<br /> NRVR-Members mailing list<br /><a rel="nofollow noreferrer" href="mailto:NRVR-Members@mail.nrvr.org" target="_blank">NRVR-Members@mail.nrvr.org</a><br /><a rel="nofollow noreferrer" href="http://server2.nrvr.org/mailman/listinfo/nrvr-members" target="_blank">http://server2.nrvr.org/mailman/listinfo/nrvr-members</a></blockquote>
</div>
<br /> -- <br />
<div class="m_-3459826233514180677ydp7c44a4f2yiv7790113869gmail_signature" dir="ltr">
<div dir="ltr">
<div>
<div dir="ltr">
<div dir="ltr"><br />
<div><em style="color: #000000; font-size: small; line-height: 16.9px; background-color: #f1f1f1;"><span style="font-family: arial,helvetica,sans-serif;">Quidquid latine dictum sit, altum viditur.</span></em></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<div id="m_-3459826233514180677ydp7c44a4f2yqt69371" class="m_-3459826233514180677ydp7c44a4f2yqt2570797925">_______________________________________________<br /> NRVR-Members mailing list<br /><a rel="nofollow noreferrer" href="mailto:NRVR-Members@mail.nrvr.org" target="_blank">NRVR-Members@mail.nrvr.org</a><br /><a rel="nofollow noreferrer" href="http://server2.nrvr.org/mailman/listinfo/nrvr-members" target="_blank">http://server2.nrvr.org/mailman/listinfo/nrvr-members</a></div>
</div>
</div>
</div>
</blockquote>
<p style="margin:0;padding:0;font-family: arial; font-size: 12pt; word-wrap: break-word;"> </p>
</div>
_______________________________________________<br /> NRVR-Members mailing list<br /><a rel="noreferrer" href="mailto:NRVR-Members@mail.nrvr.org" target="_blank">NRVR-Members@mail.nrvr.org</a><br /><a rel="noreferrer noreferrer" href="http://server2.nrvr.org/mailman/listinfo/nrvr-members" target="_blank">http://server2.nrvr.org/mailman/listinfo/nrvr-members</a></blockquote>
</div>
</div></font>