Recent flight testing on my KR-2 with CG at 14 inches and 1050 pound gross had marginal stability. When you get into those "marginal" areas, it can become quite subjective; how good is good or how bad is bad? You must weigh the airplane for the only reliable way to know what the gross weight and CG are. Highly recommend you keep the CG at 12 inches or lower for normal operations. Larry has a weighing demo scheduled at the Gathering this year; check it out.
Sid Wood Tri-gear KR-2 N6242 Mechanicsville, MD, USA ----------------------------------------------------------------------- Pierre wrote: > Does anybody have advise on maximum weight? My CG is just over 50% aft > (that > is, I am still within 2-3inches forward of the aft limit) but if I have > both > wing tanks, header tank, 30 pounds of baggage and a passenger, I seem to > be > about 75 - 100 pounds over the maximum of 1100 pounds. After fuel burn I > should come to just within the 1100 pounds for landing. My KR2S has a VW > (Dyno reading is 70hp) and I take off at 4,500ft. How critical is maximum > allowable weight? Is your CG 2"-3" forward of the "published" CG point given in the plans, or 2" forward of that, which is the recommended (through analysis and experience) location? And keep in mind that the KR2S design gross weight is 980 pounds, so your landing weight is still over gross weight. Having said that, my data plate reads 1100 pound gross, and I routinely fly at 1000 pounds, but putting a passenger in the plane leads to slow climbouts and a real difference in stability. And that's with about 125 hp near sea level. Depending on CG, you can probably fly with your plane as is, but I'd sneak up on the passenger and baggage weight during testing. I think you'll discover that you have a one seater plane if safety is a concern, which it should be. I say that based on climbout rate. You don't want to be strung out over the woods with any kind of problem that brings you down to three cylinders or even a slight loss of power on takeoff, and heavy takeoff weights with low power are the recipe for that scenario... Mark Langford ML at N56ML.com website at http://www.N56ML.com --------------------------------------------------------
