+# YikStik3
+
+## Motivation
+
+This is a "replacement" for Bdale's first L3 certification airframe,
+[YikStik](../YikStik), which was mostly lost... and a follow-on to
+[2YikStik](../2YikStik), which had one and only one "way too exciting"
+flight at LDRS 30. We recovered the nose cone, tail cone, rail buttons,
+and all of the electronics from 2YikStik. Everything else is new for this
+build.
+
+Meanwhile, Robert became interested in measuring the temperature of a nose
+cone and a fin on a rocket at speeds above Mach. This led Bdale to design
+a [TeleMetrum](http://altusmetrum.org/TeleMetrum) companion board called
+[TeleScience](http://altusmetrum.org/TeleScience) capable of hosting up to
+12 NTC thermistors for temperature data collection.
+As was the case with 2YikStik](../2YikStik), the plan is to fly two
+[TeleMetrum](http://altusmetrum.org/TeleMetrum)+[TeleScience](http://altusmetrum.org/TeleScience)
+setups, one mounted in the nose cone and one mounted in the fin can. The
+one in the fin can will be responsible for apogee deployment, and the one in
+the nose cone will handle main deployment.
+
+We will again fly a custom 98mm nose cone with the temperature sensors
+embedded in the glass layers made for us by Jeff Lane of
+[Shock Wave Rocketry](http://shockwaverocketry.com/).
+
+## Design Details
+
+* 98mm [Performance Rocketry](http://performancerocketry.com) G-10 convolute glass air frame
+* 75mm [PML](http://www.publicmissiles.com) phenolic motor mount
+* [Shock Wave Rocketry](http://shockwaverocketry.com/) fiberglass 98mm Von Karman 6:1 nose cone
+* custom fins, using 3/16 inch birch plywood laminated with carbon fiber
+ and a fibreglass sanding veil
+* 3/8 inch birch plywood centering rings and bulkheads, CNC milled, the two
+ that hold the fins are double thickness (3/4 inch) and notched for perfect
+ fin alignment.
+
+The OpenRocket design file is
+[YikStik3.ork](/rockets/airframes/YikStik3/YikStik3.ork).
+
+### Thermistors ###
+
+The temperature sensors chosen are 0.8 mm diameter glass bead NTC thermistors
+made by EPCOS, model B57540G0303F000. These were chosen because of their
+small size, and turn out to have a very fast response time to changing
+temperatures.
+
+The leads were extended with 30 gauge wire wrap wire using twisted pairs of
+black plus a color. The colored lead was insulated from the bead back over
+the solder joint using 1/16 inch heat shrink tubing. The epoxy used for the
+nose cone and fin was tested and confirmed to have essentially no
+conductivity.
+
+### Electronics ###
+
+The airframe geometry led us to decide to build two electronics bays, one in
+the airframe immediately aft of the nose cone, and the other in the fin can.
+Each bay holds a production
+[TeleMetrum](http://altusmetrum.org/TeleMetrum), a prototype companion
+board called [TeleScience](http://altusmetrum.org/TeleScience), a 1000 mAh
+LiPo battery, and a power switch.
+
+The TeleScience board supports connection of up to 12 NTC thermistors along
+with other capabilities.
+
+Installing the electronics in the fin can bay was .. interesting. More later.
+
+## Build
+
+Parts gathered during late 2011 and early 2012. Built underway in early
+March of 2012.
+
+The nose cone was custom fabricated by Jeff Lane at
+[Shockwave Rocketry](http://shockwaverocketry.com), with thermistors embedded.
+
+The fins are 3/16 inch birch ply, tapered on the leading and trailing edges,
+then covered with one layer of 5.7 oz 2x2 twill carbon fiber and a layer of
+6 oz glass as a sanding veil, all vacuum bagged with West Systems laminating
+epoxy using a kitchen food saver appliance.
+
+We're moving from the Giant Leap Rocketry 98mm Magnaframe-based Dynawind to
+G-10 glass tubing this time around. Dynawind is lighter and strong enough,
+but we want to use glass couplers this time around for more strength, and
+that leads to fit issues with the Magnaframe-based Dynawind tubing. So even
+though it's slightly heavier, we're going with an all-gladd build this time.
+We'll lose a little bit of max velocity, but hopefully it'll all hang together
+this time!
+
+The tailcone is a no-longer-available Giant Leap 98-75mm Slimline tailcone
+recovered from 2YikStik's wreckage.
+
+All rings and bulkheads were cut using a CNC milling machine from 3/8 inch
+birch plywood. The fin forward and leading edge rings are made from 3/4 inch
+thick assemblies made by laminating two such rings with wood glue, to provide
+sufficient depth for milled fin slots.
+
+Will add a pointer to build photos here once they are available.
+
+## Publicity
+
+## Flights
+
+The intended first flight of YikStik3 will be at NCR's Mile High Mayhem 2012
+on an as-yet-unreleased [Cesaroni](http://pro38.com) Pro75 6xl Imax reload
+tentatively designated 9874M2245, which is a 92.7% M with approximately
+4.4 seconds burn time. It's going to be one heck of a ride!
projects / web / gag.com / commitdiff