Monday, November 7, 2016

The Enjoyment from Fast Free Flight

This past year I spent a major amount of my model aviation time learning with competition free flight model airplanes. I still fly RC sailplanes both thermal and slope with some sport electric RC as well. My point in mentioning this is I have a fair amount of experience building and adjusting model airplanes, yet not the complete skill set for fast free flight airplanes. Adjusting the flight of the Pearl e202 E36 model has been much more challenging than the NJAPF P30 rubber model I fly. With my P30 model there has not been a single crash that I can remember, the only adjustments are with the climb and circle amounts.

Pearl E202 E36

P30 Rubber Model Easier to Trim

In previous articles I have mentioned some of the challenges I have had with my e36 model, it has crashed several times but I have been able to repair it fairly quickly. Carbon fiber reinforcement has been added in several places, I think I would do this on a new build. I thought I had the plane adjusted pretty well but this past Saturday the plane started turning to the left on launch in the climb, luckily I used a really short DT, it saved the airplane. I gave it what I thought was a very small amount of right rudder trim but it curved to the right after launch and hit the ground.

Damaged Model

The front of the pylon was smashed like it has been several times before but worse was one wingtip that was broken in many places underneath the covering. I collected the pieces and started the repair job but spent much of the afternoon flying RC gliders. The repairs were finished that evening but I also noticed the dihedral joint in the opposite wingtip was flexing easy. Now I do not know if it happened in the crash but my theory is this issue has been present and causing the model to be out of trim. I should have inspected the model before when I noticed a change in the flight pattern. My excuse was the colder temperatures I was flying it in.  There was nothing visible that you could see to spot the problem but putting any force on the joint it would be obvious.

Repaired

Flying Again 
I got out early the next morning for test flights before there was any wind. As Hank Nystrom had reminded me, I started with the shortest motor run and quickest DT. That looked good but it was really short, increased the motor run a little more and still looking good. Next I gave the DT just a little more time so I could see the transition; that looked good. Just a little longer DT as I was flying from a small flying site, it looked really good with no stall between power and glide. I was elated and it gave me back some confidence that I was again making progress.

Flying From Farm Land but Trees on Edge


For me the enjoyment in free flight models with a fast climb rate comes from the more challenging aspects adjusting the model and building it correctly to start with. It forces you to really observe the model closely when flying and theorize how it might be improved. When you watch so many power models fly at a contest it looks way too easy because you do not realize the time and effort the experienced modelers put into getting their models to fly so well.

Bill Kuhl
http://www.ideas-inspire.com

Related Articles
http://scienceguyorg.blogspot.com/2016/10/making-progress-in-e36.html
http://scienceguyorg.blogspot.com/2016/08/flying-my-e36-at-2016-nats.html
http://scienceguyorg.blogspot.com/2016/05/much-to-learn-about-e36-free-flight.html
http://scienceguyorg.blogspot.com/2015/12/electric-free-flight-test-model.html
http://scienceguyorg.blogspot.com/2016/10/oktoberflug-free-flight-contest.html
http://scienceguyorg.blogspot.com/2016/08/minnesota-free-flight-contest-near.html

Vendor Websites
http://www.texastimers.com/

http://www.pearlfreeflight.com/Buy.html


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