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+[[!tag tags/rockets]]
+I [wrote last month](YikStik)
+about my failed first attempt to achieve a "level 3" high power rocketry
+certification.  Last week, I learned that one of the commercial altimeters
+I flew for control of the ejection sequence has a firmware bug, which can
+cause premature ejection of the main parachute on flights above 10k feet!
+So it may in fact be the case that everything I did was perfect and I was
+simply the victim of a bug in software... how ironic!
+
+Yesterday, on my second certification attempt, I was successful!
+
+The rocket I flew this time was based on a 
+[Polecat Aerospace](http://www.polecataerospace.com/)
+ten inch Goblin kit.  I incorporated several modifications in my build, 
+including additional fiberglass and carbon fiber reinforcement, and a
+payload bay in the nose cone.
+
+Once again, my wife Karen graced me with a parachute sewn from the  
+[Team Vatsaas](http://www.vatsaas.org/rtv/systems/Parachutes/Chute.aspx)
+design, this time a slightly larger one in burgundy and black rip-stop nylon.
+She incorporated several design tweaks based on her experiences sewing the
+first one which we'll try to write up at some point, that allowed her to sew
+this one in less time.
+
+The motor selected was again an 
+[Aerotech](http://www.aerotech-rocketry.com)
+M1297W reload.  
+
+The launch went perfectly, and the ascent was impressive.  At apogee, the 
+nose cone separated as planned and the drogue parachute deployed.  
+Unfortunately, when the backup charge fired two seconds later, the main 
+parachute also deployed.  That wasn't intended... the main was supposed to
+deploy much lower, at 1300 feet.  Luckily, the winds were light enough that
+the rocket touched down only about a mile downrange from the launch rail, well
+within the waiver distance, and was easily recovered without damage.
+
+There are three things I'll consider changing before flying this rocket again.
+First, the chute size calculator used to design the main parachute seems way 
+off.  The actual descent rate was around 32 feet per second, while our goal was 20.  Other than that, the parachute performed admirably!
+Second, the premature deployment of the main at apogee could be cured by 
+replacing the paper taped over that parachute bay with another piston capping
+the bay and held in with a pair of shear pins.  Finally, the hard touch down
+snapped some of the nylon wire ties holding the batteries in place in the
+avionics bay.  While no damage was done, and reducing the descent rate might
+prevent it happening again, improving the battery mounting would be an easy
+upgrade.
+
+For more information, see 
+[my project page](http://www.gag.com/rockets/projects/goblin10/)
+this rocket.
+James Russell took some 
+[pictures](http://picasaweb.google.com/jamesr2/StealeyMemorialLaunchSiteHudsonRanch)
+at the launch, including 
+[a great one](http://picasaweb.google.com/jamesr2/StealeyMemorialLaunchSiteHudsonRanch#5269066826180657666)
+of the rocket under boost just leaving the launch rail.
+And Jeff Lane captured
+[video](http://cosrocs.org/all%20other%20videos/2008videos/11-15hudson/bdale_L3.mov)
+of the ascent and descent.
+
+It was a great flight and a great day, and represents a major milestone in
+our hobby rocket activities!