Hi
I have the same problem with my rolls, i cant even get a normal roll to look right.

What i have been trying to do is.

Applying rudder from 45 degrees reaching peak at 90 degrees reducing to zero at 135 degrees
applying down elevator increasing from 135 degrees reaching peak at 180 degrees and back to zero at 225 degrees
applying opposite rudder increasing from 225 degrees reaching peak 270 degrees feathering back to zero at 315 degrees
then gradually applying up elevator as appropriate as you reach upright

Am I on the right track or have I got it completely wrong?

M

Mike, I don't quite know how I came by my method, but I believe it is the 'standard' approach (whatever that means). At any rate, as I go around the 360 degrees of roll, I am blending rudder with elevator almost constantly, but not too much of either, depending on the airspeed of the model (more airspeed requires less control/correction inputs). So for instance at the 1/8 position (rolling right) I have left rudder increasing and pull elevator decreasing; at 1/4 I have left rudder maximum input (not full stick, but I stop adding rudder at 1/4 and past 1/4 start decreasing it); at 3/8 I have left rudder decreasing and push elevator increasing; at 1/2 I have rudder passing through neutral into right rudder and push elevator at maximum (again, not full stick), and so on around the clock.

Now I can't say my inputs are right on the money at these points of the roll, but they are definitely simultaneous inputs, and definitely one increasing while the other is decreasing. If it's a strong breeze across the flight path, don't ask me to explain how to wind-correct at the same time, but it's 'more of the same'.

I think I was persuaded into this approach some time back by talking with a very accomplished pilot who flies what I believe is Mode 3, with rudder and elevator on the right stick. He explained that for slow rolls,rolling circles and rolling harriers his right stick input is pretty much a stirring motion, with the stick going around in a circle or oval path (which of course means elevator is increasing as rudder is decreasing and vice versa).

When you are set up with elevator & ailerons on right stick and rudder on left stick (as I am), the coordination is something akin to patting your head and rubbing your belly simultaneously. It can be learned, but it doesn't come naturally to most folks.

I will say in all modestly I am capable of turning out a pretty straight slow roll. Sometimes, anyway.

I should also say I normally trim for slight pull on the elevator for straight & level flight. Not much, but a little, which I try to balance against the push needed to keep straight & level inverted. Where you have your CG is also a consideration in this set-up. I'm typically between 30-33% of MAC for my aerobats.

Hi
So what are the stick commands as I go round a normal roll eg 1/8, 1/4 3/8th etc points when you are doing a normal roll?

Mike

Mike, you have the general idea of the inputs, but to say you should be hitting this or that at certain points just can’t be done. There are too many other factors involved to break it down so mechanically. It’s really a feel maneuver (if such a thing exist in R/C). You need to be able to analyze what the plane is doing through the maneuver, compensating for deviations with minuet adjustments and this comes with practice.

What seems to be going wrong with your rolls?

That's a pretty good question, but the answer is not so clear-cut until you have an actual model in the air with whatever its CG, trim and mix happen to be, plus of course roll-rate and airspeed.

I will say that my half-rolls (1 of 2 from upright to inverted or inverted to upright) I find I just about always help the roll around with a nudge of top rudder. This has become pretty much automatic for me, and I never think about it when doing it.

I was coached in my early pattern days to do linked rolls, as many as I could string together, holding constant aileron all the way, and keeping on axis using just elevator pull at upright and push at inverted, nothing with the rudder. If I had tried to sneak in top rudder at the 1/4 and 3/4 points that would have made it impossible for me to practice. I had enough trouble just getting the elevator timing right, and two axial linked rolls was a great achievement for me, and three was a miracle.

When I was practicing linked rolls, I felt I could get better timing by slowing down the roll rate, and that worked for me. Pretty soon I actually found it easier to do a slow roll on tight axis than to do a regular roll. But for contests I always practiced with higher airspeed and faster roll rate, so I could just breeze through a roll with nothing but aileron and take whatever points I could get. But as time went along, I became dissatisfied with fast roll rates, and felt a slower roll was more graceful.

Even my coach admitted that when he practiced linked rolls, the guys at the field would compliment him on his rolling circles. He told me that what they didn't understand was that he was trying to roll in a straight line, but when his concentration slipped, it was easier to link rolls in a big circle than it was to roll in a straight line. I'll testify to that myself.

One exercise that will help your understanding of inputs at the 1/8 points is to fly the length of the field on a straight track, wind-corrected if necessary, on axis. I believe you'll find that some input from both rudder and elevator are needed to hold a steady, axial track with your wings steady at the 1/8, 3/8, etc. points. Consider that a V-tailed model can be a substitute for a conventional tailed model at the 1/8 points. What the V-tailed model has mixed in the linkage or TX, you have to mix with your fingers to get the same result.

When you've absorbed that, then try an eight point roll covering the length of the field, left to right then right to left. When you can do that reasonably well, let me know and I'll buy the beer.

Not too long ago on a related thread, someone quoted his old pattern coach as saying 'All rolls are slow rolls,' meaning rudder and elevator inputs on any roll. I think that's probably good advice, but it must be practiced, and the plane must be well set up and trimmed and mixed, all of which is a lengthy process involving many hours at the field.

My final word, if you are trying to learn precision aerobatics, is to learn whatever maneuver by slap dashing any rough approximation of it that you can to start off, and then work on little aspects of it one by one until you get them worked out. This takes more than one day at the field, and takes some thinking and maybe sketching at night, then practice, reflection, clear intent at every practice session.