-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Goblin 10</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book" lang="en"><div class="titlepage"><div><div><h1 class="title"><a name="id2
560049"></a>Goblin 10</h1></div><div><h2 class="subtitle">A NAR L3 Certification Rocket</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><p class="copyright">Copyright © 2008 Bdale Garbee</p></div><div><div class="legalnotice"><a name="id2815458"></a><p>
+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Goblin 10</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book" lang="en"><div class="titlepage"><div><div><h1 class="title"><a name="id2
481338"></a>Goblin 10</h1></div><div><h2 class="subtitle">A NAR L3 Certification Rocket</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><p class="copyright">Copyright © 2008 Bdale Garbee</p></div><div><div class="legalnotice"><a name="id2736747"></a><p>
This document is released under the terms of the
<a class="ulink" href="http://creativecommons.org/licenses/by-sa/3.0/" target="_top">
Creative Commons ShareAlike 3.0
</a>
license.
- </p></div></div><div><div class="revhistory"><table border="1" width="100%" summary="Revision history"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.0</td><td align="left">15 November 2008</td></tr><tr><td align="left" colspan="2">Successful certification flight at Hudson Ranch</td></tr><tr><td align="left">Revision 0.2</td><td align="left">28 October 2008</td></tr><tr><td align="left" colspan="2">Revising during flight to DC</td></tr><tr><td align="left">Revision 0.1</td><td align="left">23 October 2008</td></tr><tr><td align="left" colspan="2">Initial content, derived from YikStik</td></tr></table></div></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#id2
822757">1. Introduction</a></span></dt><dt><span class="chapter"><a href="#id2828645">2. Design</a></span></dt><dd><dl><dt><span class="section"><a href="#id2838502">Overview</a></span></dt><dt><span class="section"><a href="#id2815988">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2842401">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2823397">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2833680">Nose Cone Electronics Bay</a></span></dt><dt><span class="section"><a href="#id2812400">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2842095">Avionics</a></span></dt><dt><span class="section"><a href="#id2819216">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2826797">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2845875">Recovery System</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#id2847645">3. Construction Details</a></span></dt><dd><dl><dt><span class="section"><a href="#id2845740">Airframe</a></span></dt><dt><span class="section"><a href="#id2813144">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2834138">Avionics Bay</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2831717">4. Recovery Systems Package</a></span></dt><dd><dl><dt><span class="section"><a href="#id2847622">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2830883">Recovery Initiation Control Components</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2846528">5. Checklists </a></span></dt><dt><span class="chapter"><a href="#id2842033">6. Flight Summary</a></span></dt><dt><span class="chapter"><a href="#id2842161">7. Analysis and Conclusions</a></span></dt></dl></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2822757"></a>Chapter 1. Introduction</h2></div></div></div><p>
+ </p></div></div><div><div class="revhistory"><table border="1" width="100%" summary="Revision history"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.0</td><td align="left">15 November 2008</td></tr><tr><td align="left" colspan="2">Successful certification flight at Hudson Ranch</td></tr><tr><td align="left">Revision 0.2</td><td align="left">28 October 2008</td></tr><tr><td align="left" colspan="2">Revising during flight to DC</td></tr><tr><td align="left">Revision 0.1</td><td align="left">23 October 2008</td></tr><tr><td align="left" colspan="2">Initial content, derived from YikStik</td></tr></table></div></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#id2
744045">1. Introduction</a></span></dt><dt><span class="chapter"><a href="#id2749934">2. Design</a></span></dt><dd><dl><dt><span class="section"><a href="#id2759790">Overview</a></span></dt><dt><span class="section"><a href="#id2737277">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2763689">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2744686">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2754969">Nose Cone Electronics Bay</a></span></dt><dt><span class="section"><a href="#id2733689">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2763384">Avionics</a></span></dt><dt><span class="section"><a href="#id2740504">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2748086">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2767164">Recovery System</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#id2768933">3. Construction Details</a></span></dt><dd><dl><dt><span class="section"><a href="#id2749141">Airframe</a></span></dt><dt><span class="section"><a href="#id2754017">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2771414">Avionics Bay</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2745741">4. Recovery Systems Package</a></span></dt><dd><dl><dt><span class="section"><a href="#id2740673">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2752914">Recovery Initiation Control Components</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2748101">5. Checklists </a></span></dt><dt><span class="chapter"><a href="#id2750187">6. Flight Summary</a></span></dt><dt><span class="chapter"><a href="#id2764884">7. Analysis and Conclusions</a></span></dt></dl></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2744045"></a>Chapter 1. Introduction</h2></div></div></div><p>
This is a rocket I'm building for my second attempt at a NAR Level 3
certification flight. It's basically a Polecat Aerospace Goblin 10 kit
augmented with an additional electronics bay in the nose cone, some
NCR launch sites under their standing waivers.
The smallest reasonable motor for this rocket would be a Cesaroni
K445 or equivalent, which would yield an apogee of about 2300 feet.
- </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
828645"></a>Chapter 2. Design</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2838502">Overview</a></span></dt><dt><span class="section"><a href="#id2815988">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2842401">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2823397">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2833680">Nose Cone Electronics Bay</a></span></dt><dt><span class="section"><a href="#id2812400">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2842095">Avionics</a></span></dt><dt><span class="section"><a href="#id2819216">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2826797">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2845875">Recovery System</a></span></dt></dl></dd></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2838502"></a>Overview</h2></div></div></div><p>
+ </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
749934"></a>Chapter 2. Design</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2759790">Overview</a></span></dt><dt><span class="section"><a href="#id2737277">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2763689">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2744686">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2754969">Nose Cone Electronics Bay</a></span></dt><dt><span class="section"><a href="#id2733689">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2763384">Avionics</a></span></dt><dt><span class="section"><a href="#id2740504">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2748086">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2767164">Recovery System</a></span></dt></dl></dd></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2759790"></a>Overview</h2></div></div></div><p>
The Goblin 10 kit is a simple "four fins and a nose cone" rocket
that is short and squat, with a 98mm motor mount.
It supports dual-deploy by
centering rings, accessed by a side hatch. An additional payload bay
will be built inside the nose cone to carry experimental altimeters,
a tracking beacon, and possibly a GPS position reporting system.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2815988"></a>Rocksim File</h2></div></div></div>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2737277"></a>Rocksim File</h2></div></div></div>
This is the current working design in Rocksim format:
- <a class="ulink" href="Polecat_Goblin_10.rkt" target="_top"> Polecat_Goblin_10.rkt </a></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
842401"></a>Drawing from Rocksim</h2></div></div></div><span class="inlinemediaobject"><img src="Polecat_Goblin_10.jpg" height="450"></span></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2823397"></a>Motor Retention</h2></div></div></div><p>
+ <a class="ulink" href="Polecat_Goblin_10.rkt" target="_top"> Polecat_Goblin_10.rkt </a></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
763689"></a>Drawing from Rocksim</h2></div></div></div><span class="inlinemediaobject"><img src="Polecat_Goblin_10.jpg" height="450"></span></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2744686"></a>Motor Retention</h2></div></div></div><p>
I will include 8-24 T-nuts in the aft centering ring spaced to allow
the use of an Aeropack 98mm retainer and associated 75mm adapter.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
833680"></a>Nose Cone Electronics Bay</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
754969"></a>Nose Cone Electronics Bay</h2></div></div></div><p>
Instead of using the supplied nose cone bulkhead, I intend to cut a
custom one that would support installing a length of 98mm motor mount
from the tip of the nose to the bulkhead. With a plate cut to cover
the aft end of the airframe tube, this would form an electronics bay
capable of holding a beacon transmitter, GPS system, or other custom
electronics.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
812400"></a>Electronics</h2></div></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2842095"></a>Avionics</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
733689"></a>Electronics</h2></div></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2763384"></a>Avionics</h3></div></div></div><p>
The recovery system will feature dual redundant barometric altimeters
in the main avionics bay between the two forward motor mount
centering rings.
A third rotary switch will be used as a SAFE/ARM switch configured
to interrupt connectivity to all ejection charges in accordance with
NAR certification requirements.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
819216"></a>Stability Evaluation</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
740504"></a>Stability Evaluation</h3></div></div></div><p>
The Goblin 10 kit designers indicate
that the rocket is unconditionally stable with all motors that fit
the motor mount geometry. Since we're adding mass at both ends, by
I also note that the simulated margin of stability
in my as-built configuration is fairly close to the margin of
stability of the as-designed model.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
826797"></a>Expected Performance</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
748086"></a>Expected Performance</h3></div></div></div><p>
The Aerotech M1297W reload should carry this vehicle to just under
7000 feet AGL from Colorado Front Range launch sites. It
should reach just over 2 miles on a Cesaroni M795 moon burner
or equivalent.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
845875"></a>Recovery System</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
767164"></a>Recovery System</h3></div></div></div><p>
The recovery system will use dual redundant barometric altimeters
firing 4F black powder charges using commercial e-matches.
At apogee, a drogue chute will deploy with separation of the nose
</p><p>
The recovery system attachment points will all use 1/4 inch u-bolts
with nuts, washers, and backing plates through bulkheads.
- </p></div></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2847645"></a>Chapter 3. Construction Details</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2845740">Airframe</a></span></dt><dt><span class="section"><a href="#id2813144">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2834138">Avionics Bay</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2845740"></a>Airframe</h2></div></div></div><p>
+ </p></div></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2768933"></a>Chapter 3. Construction Details</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2749141">Airframe</a></span></dt><dt><span class="section"><a href="#id2754017">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2771414">Avionics Bay</a></span></dt></dl></div><p>
+ I have collected all of my
+ <a class="ulink" href="http://gallery.gag.com/rockets/goblin10" target="_top">
+ build photos
+ </a>
+ in one place, they may show better than I can explain how various
+ aspects of the Goblin went together.
+ </p><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2749141"></a>Airframe</h2></div></div></div><p>
The airframe tubing provided in the Polecat kit is thick cardboard tube
with a thin exterior fiberglass wrap. To increase airframe strength,
and particularly to prevent zippers, additional reinforcement seemed
curing by an inflatable child's bounce toy inside a plastic garbage
bag. The result is a substantially strengthened tube, with carbon
fiber lining from the leading edge back past the first centering ring.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
813144"></a>Nose Cone</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
754017"></a>Nose Cone</h2></div></div></div><p>
The provided nose cone bulkhead was replaced by a custom centering
ring cut from 3/8 inch birch plywood. The ring's outer diameter was
adjusted put place the ring approximately an inch forward of the end
the piece of airframe tubing. After the epoxies cured, a rotary tool
was used to cut the airframe tubing off flush with the aft surface of
the centering ring.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
834138"></a>Avionics Bay</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
771414"></a>Avionics Bay</h2></div></div></div><p>
The avionics bay walls were installed approximately 90 degrees apart
prior to installation of the motor mount assembly in the airframe.
The airframe wall was marked for a 3.5 x 6.5" access hatch centered
A suitably sized avionics sled should be possible to install and remove
through the avionics bay hatch allowing for possible future experiments
with alternative avionics.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
831717"></a>Chapter 4. Recovery Systems Package</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2847622">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2830883">Recovery Initiation Control Components</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2847622"></a>Recovery System Description</h2></div></div></div><p>
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
745741"></a>Chapter 4. Recovery Systems Package</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2740673">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2752914">Recovery Initiation Control Components</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2740673"></a>Recovery System Description</h2></div></div></div><p>
This rocket uses dual deployment.
</p><p>
The apogee event separates the nose cone from the
chute apex, with a smaller drogue chute deployed to pull off the bag
and cleanly deploy the main. The primary motivation for this is to
prevent the main chute shrouds from tangling during ejection.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
830883"></a>Recovery Initiation Control Components</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
752914"></a>Recovery Initiation Control Components</h2></div></div></div><p>
The main avionics bay between the forward two centering rings is
populated with two commercial altimeters, a PerfectFlite MAWD
and a Missile Works miniRRC2.
With a 10 foot Team Vatsaas design parachute and our
anticipated build weight, the descent rate under main
should be just over 20 feet per second.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
846528"></a>Chapter 5. Checklists </h2></div></div></div><div class="orderedlist"><ol type="1"><li>
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
748101"></a>Chapter 5. Checklists </h2></div></div></div><div class="orderedlist"><ol type="1"><li>
Planning
<div class="orderedlist"><ol type="1"><li>
Pick a club launch with suitable waiver and facilities to
flight line
</li><li>
bring the rocket to observers for post-flight inspection
- </li></ol></div></li></ol></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
842033"></a>Chapter 6. Flight Summary</h2></div></div></div><p>
+ </li></ol></div></li></ol></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
750187"></a>Chapter 6. Flight Summary</h2></div></div></div><p>
A successful level 3 certification flight occurred on 15 November 2008
at the SCORE Hudson Ranch launch facility. The motor was an Aerotech
M1297W provided by Tim Thomas of Giant Leap Motors, the igniter was
Video of the launch taken by Jeff Lane
</a></li><li><a class="ulink" href="http://www.youtube.com/watch?v=xaJnl89wfWU" target="_top">
Video of the launch taken by Jason Unwin
- </a></li></ul></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
842161"></a>Chapter 7. Analysis and Conclusions</h2></div></div></div><p>
+ </a></li></ul></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
764884"></a>Chapter 7. Analysis and Conclusions</h2></div></div></div><p>
The ascent was straighter than expected... very smooth during
the motor burn, then a couple slow rolls during coast. The two
altimeters agreed within 4 feet on the apogee. The max
-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>YikStik</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book" lang="en"><div class="titlepage"><div><div><h1 class="title"><a name="id2
391886"></a>YikStik</h1></div><div><h2 class="subtitle">A NAR L3 Certification Rocket</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><p class="copyright">Copyright © 2008 Bdale Garbee</p></div><div><div class="legalnotice"><a name="id2647249"></a><p>
- This document is released under the terms of the
+<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>YikStik</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book" lang="en"><div class="titlepage"><div><div><h1 class="title"><a name="id2
286209"></a>YikStik</h1></div><div><h2 class="subtitle">A NAR L3 Certification Rocket</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><p class="copyright">Copyright © 2008 Bdale Garbee</p></div><div><div class="legalnotice"><a name="id2541572"></a><p>
+ This document is released under the terms of the
<a class="ulink" href="http://creativecommons.org/licenses/by-sa/3.0/" target="_top">
Creative Commons ShareAlike 3.0
</a>
license.
- </p></div></div><div><div class="revhistory"><table border="1" width="100%" summary="Revision history"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.0</td><td align="left">28 October 2008</td></tr><tr><td align="left" colspan="2">
+ </p></div></div><div><div class="revhistory"><table border="1" width="100%" summary="Revision history"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.1</td><td align="left">5 December 2008</td></tr><tr><td align="left" colspan="2">
+ Remove embedded images in favor of references to gallery.gag.com
+ </td></tr><tr><td align="left">Revision 1.0</td><td align="left">28 October 2008</td></tr><tr><td align="left" colspan="2">
Recording results of first, and only, flight attempt.
</td></tr><tr><td align="left">Revision 0.5</td><td align="left">27 September 2008</td></tr><tr><td align="left" colspan="2">
Building checklists
Documenting the build process as it happens
</td></tr><tr><td align="left">Revision 0.3</td><td align="left">29 March 2008</td></tr><tr><td align="left" colspan="2">
Incorporate ideas from James Russell during initial L3CC review
- </td></tr><tr><td align="left">Revision 0.2</td><td align="left">27 March 2008</td></tr><tr><td align="left" colspan="2">Cleaned up for initial review</td></tr><tr><td align="left">Revision 0.1</td><td align="left">16 March 2008</td></tr><tr><td align="left" colspan="2">Initial content</td></tr></table></div></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#id2
634993">1. Introduction</a></span></dt><dd><dl><dt><span class="section"><a href="#id2635039">Why "YikStik"?</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2626705">2. Design</a></span></dt><dd><dl><dt><span class="section"><a href="#id2626711">Overview</a></span></dt><dt><span class="section"><a href="#id2626729">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2626743">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2626762">Airframe Tubing</a></span></dt><dt><span class="section"><a href="#id2626778">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2626789">Fins</a></span></dt><dt><span class="section"><a href="#id2678165">Centering Rings and Bulkheads </a></span></dt><dt><span class="section"><a href="#id2666934">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2669027">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2682045">Avionics</a></span></dt><dt><span class="section"><a href="#id2658585">Payload</a></span></dt></dl></dd><dt><span class="section"><a href="#id2651147">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2650942">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2668569">Recovery System</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2661729">3. Construction Details</a></span></dt><dd><dl><dt><span class="section"><a href="#id2662660">Airframe and Couplers</a></span></dt><dt><span class="section"><a href="#id2664980">Fins</a></span></dt><dt><span class="section"><a href="#id2649782">Centering Rings and Bulkheads</a></span></dt><dt><span class="section"><a href="#id2643385">Assembling the Booster Section</a></span></dt><dt><span class="section"><a href="#id2656462">Avionics Bay</a></span></dt><dt><span class="section"><a href="#id2670911">Payload Bay</a></span></dt><dt><span class="section"><a href="#id2670213">Recovery System</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2656789">4. Recovery Systems Package</a></span></dt><dd><dl><dt><span class="section"><a href="#id2656948">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2659169">Recovery Initiation Control Components</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2673956">5. Stability Evaluation</a></span></dt><dt><span class="chapter"><a href="#id2656157">6. Expected Performance</a></span></dt><dt><span class="chapter"><a href="#id2675455">7. Checklists </a></span></dt><dt><span class="chapter"><a href="#id2678315">8. Flight Summary</a></span></dt><dt><span class="chapter"><a href="#id2672899">9. Analysis and Conclusions</a></span></dt></dl></div><p>
+ </td></tr><tr><td align="left">Revision 0.2</td><td align="left">27 March 2008</td></tr><tr><td align="left" colspan="2">Cleaned up for initial review</td></tr><tr><td align="left">Revision 0.1</td><td align="left">16 March 2008</td></tr><tr><td align="left" colspan="2">Initial content</td></tr></table></div></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="chapter"><a href="#id2
529342">1. Introduction</a></span></dt><dd><dl><dt><span class="section"><a href="#id2529378">Why "YikStik"?</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2521011">2. Design</a></span></dt><dd><dl><dt><span class="section"><a href="#id2521016">Overview</a></span></dt><dt><span class="section"><a href="#id2521034">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2521047">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2521064">Airframe Tubing</a></span></dt><dt><span class="section"><a href="#id2521080">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2521091">Fins</a></span></dt><dt><span class="section"><a href="#id2572489">Centering Rings and Bulkheads </a></span></dt><dt><span class="section"><a href="#id2561257">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2563350">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2576368">Avionics</a></span></dt><dt><span class="section"><a href="#id2552908">Payload</a></span></dt></dl></dd><dt><span class="section"><a href="#id2545470">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2545265">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2562893">Recovery System</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2556052">3. Construction Details</a></span></dt><dd><dl><dt><span class="section"><a href="#id2574743">Airframe and Couplers</a></span></dt><dt><span class="section"><a href="#id2552221">Fins</a></span></dt><dt><span class="section"><a href="#id2574331">Centering Rings and Bulkheads</a></span></dt><dt><span class="section"><a href="#id2556996">Assembling the Booster Section</a></span></dt><dt><span class="section"><a href="#id2541017">Avionics Bay</a></span></dt><dt><span class="section"><a href="#id2555429">Payload Bay</a></span></dt><dt><span class="section"><a href="#id2557458">Recovery System</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2552535">4. Recovery Systems Package</a></span></dt><dd><dl><dt><span class="section"><a href="#id2566288">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2569516">Recovery Initiation Control Components</a></span></dt></dl></dd><dt><span class="chapter"><a href="#id2571153">5. Stability Evaluation</a></span></dt><dt><span class="chapter"><a href="#id2571969">6. Expected Performance</a></span></dt><dt><span class="chapter"><a href="#id2576111">7. Checklists </a></span></dt><dt><span class="chapter"><a href="#id2542552">8. Flight Summary</a></span></dt><dt><span class="chapter"><a href="#id2567211">9. Analysis and Conclusions</a></span></dt></dl></div><p>
Please note that I stopped adding photos to this document at some
point. I have many more photos of the YikStik build, but haven't
decided how best to present them yet... update coming someday!
- </p><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
634993"></a>Chapter 1. Introduction</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2635039">Why "YikStik"?</a></span></dt></dl></div><p>
+ </p><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
529342"></a>Chapter 1. Introduction</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2529378">Why "YikStik"?</a></span></dt></dl></div><p>
This is the rocket I'm designing for my NAR Level 3 certification flight.
The general idea is to build a fairly cheap rocket capable of reliably
flying this year's Aerotech level 3 special, which is an M1297W reload.
could safely fly on reloads as small as a J for economical fun. Those
altitudes mean the certification flight will need to be at a site with a
high-altitude waiver like the NCR north site.
- </p><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
635039"></a>Why "YikStik"?</h2></div></div></div><p>
+ </p><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
529378"></a>Why "YikStik"?</h2></div></div></div><p>
I've always thought the high-gloss red paint job on one of my son's rockets
when out on a launch rod in the sun looks a lot like glistening wet
lipstick.
</p><p>
Combine that with the fact that my wife who isn't fond of the stuff
refers to lipstick as "yik stick"... and the rest should be obvious.
- </p><span class="inlinemediaobject"><img src="images/lilnuke.jpg" width="338"></span><span class="inlinemediaobject"><img src="images/lipstick.jpg" width="338"></span><p>
+ </p><p>
My planned paint scheme is a bright red nosecone, gold tube, and black fin
can, which is the mental image I have of what lipstick applicators look
like, most likely from a stick my mother or one of my grandmothers had
- when I was a child. Something like the image by Calliope1 that I found
- on flickr.com.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2626705"></a>Chapter 2. Design</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2626711">Overview</a></span></dt><dt><span class="section"><a href="#id2626729">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2626743">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2626762">Airframe Tubing</a></span></dt><dt><span class="section"><a href="#id2626778">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2626789">Fins</a></span></dt><dt><span class="section"><a href="#id2678165">Centering Rings and Bulkheads </a></span></dt><dt><span class="section"><a href="#id2666934">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2669027">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2682045">Avionics</a></span></dt><dt><span class="section"><a href="#id2658585">Payload</a></span></dt></dl></dd><dt><span class="section"><a href="#id2651147">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2650942">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2668569">Recovery System</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2626711"></a>Overview</h2></div></div></div><p>
+ when I was a child.
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2521011"></a>Chapter 2. Design</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2521016">Overview</a></span></dt><dt><span class="section"><a href="#id2521034">Rocksim File</a></span></dt><dt><span class="section"><a href="#id2521047">Drawing from Rocksim</a></span></dt><dt><span class="section"><a href="#id2521064">Airframe Tubing</a></span></dt><dt><span class="section"><a href="#id2521080">Nose Cone</a></span></dt><dt><span class="section"><a href="#id2521091">Fins</a></span></dt><dt><span class="section"><a href="#id2572489">Centering Rings and Bulkheads </a></span></dt><dt><span class="section"><a href="#id2561257">Motor Retention</a></span></dt><dt><span class="section"><a href="#id2563350">Electronics</a></span></dt><dd><dl><dt><span class="section"><a href="#id2576368">Avionics</a></span></dt><dt><span class="section"><a href="#id2552908">Payload</a></span></dt></dl></dd><dt><span class="section"><a href="#id2545470">Stability Evaluation</a></span></dt><dt><span class="section"><a href="#id2545265">Expected Performance</a></span></dt><dt><span class="section"><a href="#id2562893">Recovery System</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2521016"></a>Overview</h2></div></div></div><p>
YikStik is a fairly simple "three fins and a nose cone" dual-deploy
rocket using a 75mm motor mount, 4 inch glass-wrapped phenolic airframe
with zipperless fin can, plastic nose cone, plywood fins,
The primary electronics bay will be designed to
hold two altimeters, and a distinct payload bay may carry an
experimental altimeter, GPS receiver, and downlink transmitter.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2626729"></a>Rocksim File</h2></div></div></div>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2521034"></a>Rocksim File</h2></div></div></div>
This is the current working design in Rocksim format:
- <a class="ulink" href="YikStik.rkt" target="_top"> YikStik.rkt </a></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
626743"></a>Drawing from Rocksim</h2></div></div></div><span class="inlinemediaobject"><img src="images/YikStik.jpg"></span></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2626762"></a>Airframe Tubing</h2></div></div></div><p>
+ <a class="ulink" href="YikStik.rkt" target="_top"> YikStik.rkt </a></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
521047"></a>Drawing from Rocksim</h2></div></div></div><span class="inlinemediaobject"><img src="YikStik.jpg"></span></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2521064"></a>Airframe Tubing</h2></div></div></div><p>
I intend to cut the airframe components from two 48 inch lengths of
98mm Giant Leap Dynawind tubing. The 30 inch main bay and 18 inch drogue
bay will be cut from one length, while the 33 inches of fin can, 2 inches
of electronics bay, and 8 inches of payload bay will be cut from the
second.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
626778"></a>Nose Cone</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
521080"></a>Nose Cone</h2></div></div></div><p>
I intend to use a Giant Leap "Pinnacle" 3.9 inch nose cone.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
626789"></a>Fins</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
521091"></a>Fins</h2></div></div></div><p>
The fins are designed from scratch, and I intend to build them up from
two layers of 1/8 inch birch plywood, three layers of carbon fiber, and
two layers of 6 oz glass. The stack will be glass, carbon fiber,
The airframe will be slotted to allow the completed motor mount / fin
assembly to be inserted from the rear, with fillets of epoxy applied
inside and outside the airframe after insertion.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
678165"></a>Centering Rings and Bulkheads </h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
572489"></a>Centering Rings and Bulkheads </h2></div></div></div><p>
All centering rings and bulkheads will be custom machined from 3/8 inch
birch plywood using my 3-axis CNC milling machine. Some rings will use
laminated pairs of 3/4 inch total thickness to enable use of threaded
inserts for 1/4-20 rail button screws or deep routing for fin alignment
slots.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
666934"></a>Motor Retention</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
561257"></a>Motor Retention</h2></div></div></div><p>
I will embed three 8-24 T-nuts in the aft centering ring spaced to allow
the use of home-made Kaplow clips to retain 75mm motors.
The same holes may be used to attach custom motor mount adapters for
smaller diameter motors.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
669027"></a>Electronics</h2></div></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2682045"></a>Avionics</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
563350"></a>Electronics</h2></div></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2576368"></a>Avionics</h3></div></div></div><p>
The recovery system will feature dual redundant barometric altimeters
in an electronics bay similar to the LOC design located between the
drogue and main parachute bays.
Each altimeter will have a separate battery and power switch. A 4PDT
slide switch will be used as a SAFE/ARM switch configured to interrupt
connectivity to the ejection charges.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
658585"></a>Payload</h3></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2
552908"></a>Payload</h3></div></div></div><p>
I hope to fly
<a class="ulink" href="http://altusmetrum.org/" target="_top">
my own altimeter design
This is not essential to fly,
but could make recovery simpler and would just be fun to fly if I can
get it all working and suitably ground and/or flight tested in time.
- </p></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
651147"></a>Stability Evaluation</h2></div></div></div><p>
+ </p></div></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
545470"></a>Stability Evaluation</h2></div></div></div><p>
This design has been thoroughly analyzed using
<a class="ulink" href="http://www.apogeerockets.com/rocksim.asp" target="_top">
RockSim
</p><p>
These simulations will be refined as the build proceeds and as-built
stability verified before flight.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
650942"></a>Expected Performance</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
545265"></a>Expected Performance</h2></div></div></div><p>
The Aerotech M1297W reload should carry this vehicle without ballast
to just over 14 thousand feet AGL. It should make over 16 thousand
feet AGL on an M1850W, and should fly stably to roughly 2.5k feet AGL
If the cert succeeds, then I might try an optimal mass
flight sometime later on an M1850W or equivalent "bigger M"
reload to join the "three mile club".
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
668569"></a>Recovery System</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
562893"></a>Recovery System</h2></div></div></div><p>
The recovery system will use dual redundant barometric altimeters firing
black powder charges.
At apogee, a drogue chute will deploy from just forward of the fin can,
of 1/2 inch tubular kevlar, bonded to the motor mount.
If available, a screw-eye attached to the forward motor closure may be
used instead of or in addition to this recovery attachment loop.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2661729"></a>Chapter 3. Construction Details</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2662660">Airframe and Couplers</a></span></dt><dt><span class="section"><a href="#id2664980">Fins</a></span></dt><dt><span class="section"><a href="#id2649782">Centering Rings and Bulkheads</a></span></dt><dt><span class="section"><a href="#id2643385">Assembling the Booster Section</a></span></dt><dt><span class="section"><a href="#id2656462">Avionics Bay</a></span></dt><dt><span class="section"><a href="#id2670911">Payload Bay</a></span></dt><dt><span class="section"><a href="#id2670213">Recovery System</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2662660"></a>Airframe and Couplers</h2></div></div></div><p>
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2556052"></a>Chapter 3. Construction Details</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2574743">Airframe and Couplers</a></span></dt><dt><span class="section"><a href="#id2552221">Fins</a></span></dt><dt><span class="section"><a href="#id2574331">Centering Rings and Bulkheads</a></span></dt><dt><span class="section"><a href="#id2556996">Assembling the Booster Section</a></span></dt><dt><span class="section"><a href="#id2541017">Avionics Bay</a></span></dt><dt><span class="section"><a href="#id2555429">Payload Bay</a></span></dt><dt><span class="section"><a href="#id2557458">Recovery System</a></span></dt></dl></div><p>
+ I have collected all of my
+ <a class="ulink" href="http://gallery.gag.com/rockets/yikstik" target="_top">
+ build photos
+ </a>
+ in one place, they may show better than I can explain how various
+ aspects of YikStik went together.
+ </p><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2574743"></a>Airframe and Couplers</h2></div></div></div><p>
The tubing for the airframe, couplers, and motor mount was all cut
using a carefully aligned and adjusted power mitre saw, and the ends
lightly sanded to remove rough spots.
bay were cut from the second. The three couplers for the fin can,
electronics bay, and payload bay were cut from Giant Leap 98mm phenolic
coupler stock. And the motor mount was cut from Giant Leap 75mm
- phenolic airframe stock. This photo shows the airframe tube on the
- left, the motor mount in the middle, and the coupler sections on the
- right. Note that the motor mount is the longest piece because of
+ phenolic airframe stock.
+ Note that the motor mount is the longest piece because of
the zipperless design with full-length motor mount.
- </p><span class="inlinemediaobject"><img src="images/hpim2719.jpg" width="405"></span><p>
+ </p><p>
The airframe tubing selected includes a wrap of 10oz glass in epoxy
- over the base phenolic tubing (visible in the previous photo as a
- shine on the outside of the tubing), but the coupler stock is unreinforced.
+ over the base phenolic tubing (visible in some photos as a
+ shine on the outside of the tubing),
+ but the coupler stock is unreinforced.
To ensure the couplers can handle the anticipated loading, I reinforced
each with one layer of interior carbon fiber, using the "kitchen
vacuum bagging" technique documented by
after reinforcing to get "perfect" ends. The technique worked
marvelously otherwise, and the resulting couplers look and should work
great!
- </p><span class="inlinemediaobject"><img src="images/hpim2723.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2757.jpg" width="495"></span></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2664980"></a>Fins</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2552221"></a>Fins</h2></div></div></div><p>
Six pieces of 1/8 inch birch plywood were stacked, edge-aligned on what
would be the fin root edge, and clamped. The outline of the fin design
was marked in pencil, and three 1/8 inch holes drilled through the
blanks together while making the initial cuts, so that they would all be
matched in size. The clamps were removed to avoid interference
during cutting. The fin outline was then cut using a radial arm saw.
- </p><span class="inlinemediaobject"><img src="images/hpim2691.jpg" width="495"></span><p>
- A router table with 1/8
- in roundover bit was then used to round over the outer edge, 3 blanks on
+ </p><p>
+ A router table with 1/8 inch
+ roundover bit was then used to round over the outer edge, 3 blanks on
one side and three on the other. This edge might have been left square,
but I prefer the look and feel of rounding. The router table with a 1/2
inch diameter straight cutting bit and a fin beveling jig was used
to impart a 10-degree bevel on the leading and trailing edge of each fin
blank, again 3 on one side and three on the other. The resulting 6
- blanks thus form 3 pairs of fin components with a modified airfoil shape.
- </p><span class="inlinemediaobject"><img src="images/hpim2700.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2704.jpg" width="495"></span><p>
+ blanks thus form 3 pairs of fin components with a modified
+ airfoil shape.
+ </p><p>
The fin assembly started with a simple lamination of two layers of ply
sandwiching a layer of carbon fiber. Each fin used "one pump" of West
Systems epoxy and the stack was vacuum bagged using the Foodsaver with
wide bagging material. To keep everything flat while the epoxy cured,
the stack of fins was sandwiched between two unused extra shelves for
- a storage cabinet I had on hand (particle board covered in laminate, very
+ a storage cabinet I had on hand
+ (particle board covered in laminate, very
flat and smooth, nearly inflexible at this loading), and stacked with
about 75 lbs of loose barbell weights.
</p><p>
1-2mm in the longest axis. The other two are nearly perfect. Light
sanding should allow me to match them before laminating the outer layers
of carbon fiber and glass.
- </p><span class="inlinemediaobject"><img src="images/hpim2803.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2805.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2811.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2816.jpg" width="495"></span><p>
+ </p><p>
After the fins cured, they were bulk sanded with medium and fine
sandpaper and an electric palm sander. Final sanding of the leading
and trailing edges was done using 400 grit paper on a flat surface,
sides were done one at a time and allowed to cure before proceeding.
The results look good, and in combination with internal and external
airframe filets should yield a super-strong fin can.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
649782"></a>Centering Rings and Bulkheads</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
574331"></a>Centering Rings and Bulkheads</h2></div></div></div><p>
Pairs of 3/8 inch birch plywood blanks were laminated using Titebond
wood glue and clamped while curing to form 3/4 inch blanks for centering
rings. From a strength perspective, 3/8 inch should suffice, but there
are two reasons for going with thicker blanks in some places. The first
is that the rail buttons chosen use 1/4-20 mounting screws, and threaded
- inserts in that size are nearly 3/8 inch outside diameter (and thus would
+ inserts in that size are nearly 3/8 inch outside diameter
+ (and thus would
tear up a ring only 3/8 inch thick on insertion). The second is that I
like to mill slots in the centering rings on each end of the fins to
"lock" the fins into position. Doubling the blanks used to cut those
rings will allow me to cut 1/4 inch deep fin slots and still have a half
inch of unmolested wood in the rings for strength.
- </p><span class="inlinemediaobject"><img src="images/hpim2689.jpg" width="495"></span><p>
- </p><span class="inlinemediaobject"><img src="images/hpim2690.jpg" width="495"></span><p>
+ </p><p>
The aft centering ring and the one just aft of the zipperless
coupler section were edge-drilled for the installation of brass
1/4-20 threaded inserts to hold rail buttons. The inserts were
locked in place with epoxy, then ground down until nothing protruded
beyond the OD of the ring.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
643385"></a>Assembling the Booster Section</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
556996"></a>Assembling the Booster Section</h2></div></div></div><p>
The forward two centering rings were installed on the MMT using
JB Weld high-temperature epoxy, and incorporating an aircraft cable
loop for recovery system retention since there just wasn't room for
motor mount and zipperless-design coupler tubing was filled with epoxy
and milled glass. Minor gaps in the airframe behind each fin were
filled with epoxy clay.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
656462"></a>Avionics Bay</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
541017"></a>Avionics Bay</h2></div></div></div><p>
The avionics bay contains the two commercial altimeters used to
record information about the flight and deploy the drogue and main
recovery systems. It is constructed of a piece of Giant Leap 98mm
formula for a bay over 100 cubic inches the answer is 0.261 inches.
The closest standard drill size, which happens to split the difference,
is 0.250 inches. Easy enough!
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
670911"></a>Payload Bay</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
555429"></a>Payload Bay</h2></div></div></div><p>
The construction of the payload bay is very similar to the avionics
bay, except that there is a hard-epoxied rear bulkhead, and only one
screw ring to hard-mount the nose cone. The forward end of the
anticipation of extending downlink antennas above the carbon fiber
reinforcement in the coupler and into the nose cone, since carbon
fiber is opaque to RF.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
670213"></a>Recovery System</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
557458"></a>Recovery System</h2></div></div></div><p>
Pre-sewn 1/4 inch tubular kevlar harness sections were purchased
from Giant Leap, along with a small kevlar deployment bag and two
kevlar chute protectors.
</p><p>
The main parachute will be sewn from 1.9 oz rip-stop nylon purchased
from the
- <a class="ulink" href="http://creativecommons.org/licenses/by-sa/3.0/" target="_top">
+ <a class="ulink" href="http://www.milloutletfabric.com/" target="_top">
Mill Outlet Fabric Shop
</a>
in Colorado Springs. Using the spreadsheet from
and its main charge at 900 feet. Thus the MAWD is primary and the
miniRRC2 is the backup. Since the M1297W has a burn time of about
5 seconds, mach inhibit is programmed on both altimeters to 8 seconds.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
656789"></a>Chapter 4. Recovery Systems Package</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2656948">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2659169">Recovery Initiation Control Components</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2656948"></a>Recovery System Description</h2></div></div></div><p>
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
552535"></a>Chapter 4. Recovery Systems Package</h2></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="section"><a href="#id2566288">Recovery System Description</a></span></dt><dt><span class="section"><a href="#id2569516">Recovery Initiation Control Components</a></span></dt></dl></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2566288"></a>Recovery System Description</h2></div></div></div><p>
This rocket uses dual deployment.
</p><p>
The apogee event separates the
The anchor points are all 5/16 inch u-bolts, except for on the booster
which is equipped with an embedded loop of 3/16 inch stainless aircraft
cable. All connections are made with suitable quick-links.
- </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
659169"></a>Recovery Initiation Control Components</h2></div></div></div><p>
+ </p></div><div class="section" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2
569516"></a>Recovery Initiation Control Components</h2></div></div></div><p>
The LOC-style avionics bay between the main and drogue bays is
populated with two commercial altimeters, a PerfectFlite MAWD
and a Missile Works miniRRC2.
the designers of this chute pattern, sanity checked using the descent
rate tables of similar commercial parachute designs, like those from
The Rocketman.
- </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
673956"></a>Chapter 5. Stability Evaluation</h2></div></div></div><p>
+ </p></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
571153"></a>Chapter 5. Stability Evaluation</h2></div></div></div><p>
Simulation using Rocksim v8 with a variety of motors showed that the
rocket is unconditionally stable with all motors likely to be flown.
The worst-case stability among 75mm motors is actually with the
The smallest motor I can conceive of flying in this rocket (a Cesaroni
J285) would leave us overstable with margin 3.79 on the way to about
1800 feet apogee.
- </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
656157"></a>Chapter 6. Expected Performance</h2></div></div></div><p>
+ </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
571969"></a>Chapter 6. Expected Performance</h2></div></div></div><p>
On the certification flight, using an Aerotech M1297W reload and
associated hardware, the anticipated apogee is round 14,700 feet. This
is just under 75% of the NCR North Site standing waiver of 20,000 feet.
add description of anticipated flight profile here, including launch
weight, estimated drag coefficient, velocity leaving the rail, max
expected velocity, altitude, and acceleration
- </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
675455"></a>Chapter 7. Checklists </h2></div></div></div><div class="orderedlist"><ol type="1"><li>
+ </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
576111"></a>Chapter 7. Checklists </h2></div></div></div><div class="orderedlist"><ol type="1"><li>
Planning
<div class="orderedlist"><ol type="1"><li>
Pick a club launch with suitable waiver and facilities to
gather up and roughly re-pack recovery system for return to flight line
</li><li>
bring the rocket to observers for post-flight inspection
- </li></ol></div></li></ol></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
678315"></a>Chapter 8. Flight Summary</h2></div></div></div><p>
+ </li></ol></div></li></ol></div></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
542552"></a>Chapter 8. Flight Summary</h2></div></div></div><p>
YikStik was flown on an M1297W on Saturday morning at NCR's Oktoberfest
2008. The boost was beautiful. Unfortunately, we lost visual as the
rocket climbed into high clouds near apogee. Radio tracking signals
</p><p>
Reward if returned posters were placed in the area during the week
following the launch but have elicited no useful reponses yet.
- </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
672899"></a>Chapter 9. Analysis and Conclusions</h2></div></div></div><p>
+ </p></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="id2
567211"></a>Chapter 9. Analysis and Conclusions</h2></div></div></div><p>
Consideration of how the nose cone ended up where it did suggests
we may have had an apogee deployment of the main, perhaps due to
stress on the shear pins before launch, during boost, or during
projects / web / gag.com / commitdiff
