John Lange wrote: >>> Is there a way to increase the useful load by 50 pounds? > Sorry, we are looking at a KR2 that is partially built. Has > fuselage, tail and stabilizer built, no start on the wings yet.
Lots of folks have built KRs and simply placarded them at 1100 pounds or more. There's evidence that the spars and the rest of the plane can handle that easily. It's up to you, as the builder, to declare the gross weight when you get it inspected and fill out the airworthiness paperwork. You could also build it by the plans and consider it "utility category". If you wanted to make it "Light Sport" compatible, you could add several inches to the wing length to get the gross weight to wing area ratio to fit that category. We only miss the stall speed by one or two knots. If you add 50 pounds to the gross weight, it might be a foot added to each wing. Check the web for the equation, which involves lift coefficient of the wing, air density, gross weight, and wing area. Plenty of ways around this problem, but don't fall into the trap of "beefing" anything up. This plane doesn't need it, unless you hang a very heavy engine off the firewall, and even then, the reinforcements required are minimal. Mark Langford ML at N56ML.com http://www.n56ml.com
