KRNetters OK, hear me out on this one for one second: First remembering that the KR is one of the easiest aircraft to modify, and there has never been a KR crashed due to a structural failure.
The KR has a double 5/8ths spruce Upper Longerons, a single 5/8 ths lower longeron. 3/32nd plywood outer skin, and 1/4 inch plywood firewall support structure. What if: 1.) Added an additional 5/8 piece to the upper Longerons 2.) Double the lower longerons aft to behind the rear spar and add 2 ea 5/8th intercostals from the firewall to the front spar. 3.) Instead of a 3/32 plywood floor between the firewall (under the rudder pedal support) and the front spar, use 1/4 inch 45 degree bias plywood. 4.) Add a 3/32 plywood inner skin from the firewall to the instrument panel, and 1/4 inch lower firewall gusset (like the existing upper gussett in the 2S plans) and a 1/4 inch plywood doubler on the inner forward and rear faces of the front spar. 5.) Add 18 inches to each wing to increase the wing span by 3 ft (from 23 to 26) (additional wing area to handle the increased engine weight) 6.) Increase the rudder / vertical stab area by 25% 7.) Increase the landing gear strut thickness by 20% By doing these 7 things, the KR-2S should be able to handle the additional loads imposed by a heavier, more powerful engine. Essentially, I've created a torque box on the belly, and fuselage sides. This should come close to doubling the load carrying ability of the fwd structure. The added structural weight would be less than 30 pounds. For a total increase in gross weight of 67 pounds (over a corvair or Subaru). I think a weight gain of 67 pounds, with the benefit of 30 more useable horsepower, and a gob more torque is reasonable. Another benefit is it's a aircraft engine. ===== Scott Cable KR-2S # 735 Wright City, MO s2cab...@yahoo.com __________________________________ Do you Yahoo!? Yahoo! Hotjobs: Enter the "Signing Bonus" Sweepstakes http://hotjobs.sweepstakes.yahoo.com/signingbonus