ORIGINAL: UMD Pilot
Thank you both for the help,
krayzc-RCU:
Thank you for the link to the trimming guidelines. I will definitely reference this for setting up my next model.
bubbagates:
Thank you as well for your detailed response. Almost everything you said makes sense. I am just still having a hard time getting around how the airplane yaws more or less depending on attitude. I would seem like it would do one thing in all positions. This seems to not be the case. Could you touch on this some more?
Thanks,
-Matt
Matt,
You will understand it once you see it and learn to trim (correct) for it. Think of it this way, if you are flying slow, say right near the stall, you need more elevator to maintain level flight and more aileron to bank the plane, but as the plane gains speed you need less input.
Now, think of the rudder like it is used in a boat. It steers the nose of the boat left or right, exact same thing for a plane. As the plane slows, the rudder is less effective but if you are holding full power, as you normally would in a vertical climb, the torque or the spinning prop starts to pull the nose to the left. remember back in high school you learned about Newton's third law of motion, for every action there is an equal and opposite reaction, It certainly applies here as well. The prop is spinning clockwise when viewed from the pilots seat (sitting in the plane facing front). That big spinning thing, according to Newton's law, will now try to pull the nose in the opposite direction because you are slowing in the climb and the rudder can no longer overcome the big spinning thing out front unless you add more rudder. Well, we as pilots like to do as little work as possible so what we will do is move the engine in such a way that helps cancel out the torque and to do this you add a bit of right thrust. This does two things, it helps eliminate some torque and also moves the propwash further back so less of it is striking the rudder
I always suggest to my students that want learn more about how a plane flies is to buy a book that was written several years ago (early to mid 50's) called Stick and Rudder. I was given a copy of it when I learned to fly full scale aircraft in the mid 70's. It explains aerodynamics in a very easy to read format. You just have to get past some of the terminology like the elevators are called flippers in the book.
Here's a link to amazon for the book
[link=http://www.amazon.com/Stick-Rudder-Explanation-Art-Flying/dp/0070362408/ref=pd_bbs_sr_1/104-5991507-4843909?ie=UTF8&s=books&qid=1193061582&sr=8-1]Stick and Rudder[/link]