Pietenpol-List: Recent question about the Riblet airfoil angle ofattack
Posted: Tue Jul 15, 2014 9:00 am
Original Posted By: "Cuy, Michael D. (GRC-LME0)[Vantage Partners, LLC]"
Fellow Pietenpolers,Re recent comments about the Riblet airfoil on a Piet.Last year at Broadhead, I gave a forum comparing my built to the plans long fuselage Pietenpol with my friend Don Harpers extended length fuselage Pietenpol built to the plans EXCEPT with the Riblet 612 airfoil along with all the data we learned during the test flying. [ Maybe someone has a hard copy of the information I presented. Maybe they might share with everyone. I'm not sure I kept a copy.]I don't want to try and repeat the forum information here again, nor start an argument As has been said many times, READ THE ARCHIVES The detailed information is there.To answer two questions, here is what we did because there was no information avaliable at that time.1. We both used the Pietenpol plans information to build the cabane struts. The front struts are 1" longer than the rear struts.We also did what most builders do and that was make both front and rear struts 2" longer than the plans call for so the front passenger can get in and out easier. Per the plans, this should give 2 degrees angle of attack.2. Both wings were assembled upside down with the bottom of the ribs against the bottom of the spars. Without going into a very long repeat of the test flight numbers, both planes are flying well. I have about 300 hrs on my plane and Don has about 70 hrs on his. Both planes have a trim system consisting of a bunji cord and adel clamp that slides up and down the control stick for pitch changes. Simple and works well.Anytime you make a throttle change, you also have to make a trim change.My suggestion is....Use either airfoil... build it to the plans ....and it will fly great. P. F.________________________________________________________________________________
Fellow Pietenpolers,Re recent comments about the Riblet airfoil on a Piet.Last year at Broadhead, I gave a forum comparing my built to the plans long fuselage Pietenpol with my friend Don Harpers extended length fuselage Pietenpol built to the plans EXCEPT with the Riblet 612 airfoil along with all the data we learned during the test flying. [ Maybe someone has a hard copy of the information I presented. Maybe they might share with everyone. I'm not sure I kept a copy.]I don't want to try and repeat the forum information here again, nor start an argument As has been said many times, READ THE ARCHIVES The detailed information is there.To answer two questions, here is what we did because there was no information avaliable at that time.1. We both used the Pietenpol plans information to build the cabane struts. The front struts are 1" longer than the rear struts.We also did what most builders do and that was make both front and rear struts 2" longer than the plans call for so the front passenger can get in and out easier. Per the plans, this should give 2 degrees angle of attack.2. Both wings were assembled upside down with the bottom of the ribs against the bottom of the spars. Without going into a very long repeat of the test flight numbers, both planes are flying well. I have about 300 hrs on my plane and Don has about 70 hrs on his. Both planes have a trim system consisting of a bunji cord and adel clamp that slides up and down the control stick for pitch changes. Simple and works well.Anytime you make a throttle change, you also have to make a trim change.My suggestion is....Use either airfoil... build it to the plans ....and it will fly great. P. F.________________________________________________________________________________