John, I have the same problem with my KR-2: Always have to hold forward stick. Trim tab does work as I can feel changes in the stick force as the trim control is moved over the range, but still have to hold forward stick. Suggestions to increase the negative incidence of the horizontal stabilizer does defy all logic. Best I can figure is the Center of Lift for my RAF48 airfoil is about 2 inches forward of the assumed design number. That would make the airplane fly as if it were tail heavy. No manner of increasing the Horz. Stab incidence will cure that. My point here is: The plans and design numbers are wrong for the KR-2 using the RAF48 airfoil. The construction solution would be to move the entire fuselage forward 2 inches in relation to the wing; not practical for an already built KR-2. After the fact solution would be to add ballast to the nose. Or you could install a bigger engine. For my KR-2 I am revising the usable cg range: instead of 8 to 16 inches, it will be 6 to 14 inches. Mid range will be 10 inches. Working the Excel weight and balance numbers with the revised cg range, I would need 35 pounds at the spinner or 60 pounds at the firewall. Right now I am installing ballast weights at several locations on the engine and engine mount; total will be 50 pounds. A Corvair engine is starting to look good.
Sid Wood Tri-gear KR-2 N6242 Mechanicsville, MD, USA ----------------------------------------------------------------------- Well, it finally came together for me. N5391M made its second flight this afternoon. I'm not counting the "other" first flight a few years ago because the landing wasn't so good. Anyway after 2 PIO excursions on takeoff, I had a pretty nice .9 hour ride from my 2000' grass strip OR81 to MMV, site of the 2015 KR Gathering. I had to do a go-around on my first approach but the second approach was reasonable and lead to a safe landing. I tucked it into a hanger and caught a ride home with Jerry Van Grunsven in his RV8A, 1 of my 2 chase planes. I now really understand Flesner's YeeHaws! I belted out 2 of those and it sure added to the fun. Right now I want to digest a few things more fully before I post what I've learned. Until then, I want to express my deep gratitude to everyone on the list and especially, Mark Langford, Dan Heath and Oscar Zuniga for their ongoing support for my efforts. John Bouyea N5391M/ KR2 OR81/ Hillsboro, OR ------------------------------ During my entire flight today, I had to hold forward pressure on the stick. This made my takeoff more exciting than it needed to be while I figured that issue out. Landing became more an issue of reducing some forward pressure as opposed to increasing back pressure. I'll head into published readings about this imbalance and specifically how to cure it. I'm pretty sure my weight and balance is correct and with pilot and fuel loaded, I'm 3.5" aft of the forward-most CG. That leaves the trim tab "neutral position" is set incorrectly or it's just too darn small. I'm taking tools to MMV tomorrow to make what adjustments I can before further flight. Can anyone comment on facing & curing the same problem in their KR? Thank you. John Bouyea ------------------------------
