At 07:28 AM 5/9/2006, you wrote: >Personal Olá, I am writing of Brazil. Would like >to know which the profile of the airfoil one >that he is more used in kr-2s? Raf-48? AS5046? >In case that it modifies airfoil the necessary >one to modify the empennage? Somebody already >placed Droop in the wings of kr-2s? I intend to >gain more stability in low speeds. Debtor. Vinicius. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
I've not seen a post to the net answering your questions so I will offer my opinion based on my observations of KR builders. Which airfoil is more used? Many KRs are flying with the RAF48 and fly well. Most builders that have their wings built (RAF48) are continuing with the RAF48. Those builders that have not yet built their wings are generally switching to the new airfoil. The performance of the two airfoils on the low end are very similar in speeds with the advantage of the new airfoil being on the high end during cruise. The only change to the empennage is in the location of the rear spar. Stability in the low speed range seems to be good with both airfoils when some amount of washout is incorporated regardless of the wing tip design. Go to http://www.N56ML.com for the complete story of the new wing. Mark Langford's setup of incidence and washout seems to be the new "baseline" for the new airfoil. He has 200+ hours of testing now with excellent results. You may consider using the standard aileron and flap / bellyboard setup rather than Mark's design for simplicity of building. I hope this answers your questions. If not, re-post to the net. Larry Flesner
