Member Article
This Is Not a Build Article – It Is a Rebuild Article {Editor’s note – This article was submitted by Mark Barnett, D5, back in February of 2017. Enjoy!} A few K Factor readers have been critical of some of us district VPs for writing about our latest building project in order to have subject matter to meet the monthly deadline. They want wonderful, insightful and interesting articles about pattern aerobatics. Well let me invite them to write a monthly article about pattern in the frozen north in the winter. Building is just about all there is going on right now around here, but this is not a build article.
You recall in late May that my second Lightning with Spark wings went down hard at the bottom of a figure M maneuver due to an unexplained loss of power and control. I described this to you in my July K Factor article. I resolved to rebuild the Lightning with Spark wings. Following the crash, my first Lightning served out the pattern season with honor and is still flying today with about 1500 total flights. However, the Spark of Lightning flew way
better with no roll coupling in knife edge it had to be rebuilt. After the crash, an autopsy of the wreckage showed the fuselage was splintered to the back of the canopy, but the rudder had only minor damage. The canopy was destroyed, but the latches were reusable and I had the fiberglass canopy mold I had used to make it with. One stab had minor damage to the leading edge and the other was intact. One wing had leading edge damage in 3 spots and the other wing had sheeting and root rib damage including loss of both wing bolts and the adjuster pin. The wing tube, ailerons the majority of both wings and wing tips were undamaged. Therefore, if I built a new fuselage and canopy, the rest could be repaired and the Spark of Lightning could rise like a phoenix from the rubble and fly again. It could probably be ready before our trip to Arizona in February if I got my butt moving. This became my quest.
Competition balsa was purchased at Sig Manufacturing in Montezuma, Iowa where I was allowed to hand weigh each piece to get the lightest weight competition balsa. This is one advantage of living within 2 hours of a balsa supplier. Build tables were cleared of old unfinished projects. The fuselage jig and build board were located and set up. The first jig support piece was modified for the front mount Pletty Advanced motor. A short kit for the Lightning fuselage was ordered from Eureka Hobbies. Some parts were modified or completely rebuilt to make them stronger or slightly different shape from the original design. For example, the ears on former #2 were modified for the Pletty motor. Some formers were laminated with carbon fiber cloth or tissue to strengthen them. The landing gear plate was remade from Dragon board and extended to the next former to help prevent rotation. I also planned to use fiber glass tapes as a sling around these landing gear extensions to bind them to the fuselage sides. Many of
November 2020 K-Factor | 5
