Originally Posted by
drac1
1. You're assuming what is said in post #10 is correct and you know what they say about theory versus what actually happens in practise.
2. The size of the loop has nothing to do with it. Of course if the model gets too slow you will need to push down elevator to try to keep the loop round, but by that time it's too late and all you can do is add power and try to salvage as much of the maneuver as you can, but it won't be round. This is nothing more than pilot error. To perform an inside loop well, everything has to be right.
The size of the loop has to be such as to match the size and power of the model. The speed of the model has to be right and elevator inputs have to be made at the right time and correct amount to keep the loop round. That's why it's called, precision aerobatics. Get all these things right and the model will always be in a positive G condition.
I 110% agree that the above is an exact and correct analysis
except for "The size of the loop has nothing to do with it." Now maybe it does have nothing to do for it for any practical loop size in competition-sized loop but I don't care if you are flying a micro indoor foamie or an F15. If the loop is large enough
in relationship to airspeed, the plane will pull negative Gs at the top. Forgetting pattern, I know you know a gazillion times more about pattern than I do, I'm just talking physics here.
So take this comment "if the model gets too slow you will need to push down elevator". and change it do "if the model gets too slow in relationship to the size of the loop you will need to push down elevator" and all the physicists will be happy.
Now being that I don't know all that much, okay pretty much nothing, about the capabilities of a 2m plane, maybe a loop that big would be 1100' high and you couldn't even see the plane to fly it in that loop. So maybe indeed it is mostly theory and doesn't apply for practical flying.
In any case, your comments are well taken and I will take heed. I do believe the issue I have is related to airspeed going into the top segment of the loop and that's something I intend to work on.
(Hey, this thread is now in the top 15 so I guess I didn't start that sucky a thread.)
-l2t aka Ken