RE: GoPro HD 2 & HK Bixler ARF- upgrades needed?
Bixler upgrades
HobbyKing has come out with an "upgraded" Bixler 2 sailplane and the videos I've seen are most impressive. HK has apparently learned from the original Bixler design and made significant changes. They include a longer nose (to move the batteries forward) and in turn moved the CG forward (a problem with the original Bixler). Also they increased the wing area, allowing increased battery weight and FPV capacity, and added real hinges to the rudder and elevator (they were getting beat-up by the prop wash). They also increased the tail length.
I placed my order for a plane "kit" for just under $40.00 US today and will let you all know how it works out.