Rolls How to?
 

Hi
I can do a reasonable fist of most of the manoeuvres needed for me to have a go at Pattern but the one that has me beat is the Roll.
My question is a normal roll should take about 2 seconds to complete. Should i use only elevator( approaching and through the inverted portion) or should i use rudder as well as i approach the Knife edge portions?

Mike

RE: Rolls How to?
 

Unless you're doing a fairly rapid roll, you will need to learn the use of rudder during the roll. 2 seconds is a relatively slow roll. The AMA slow roll definition is 3 seconds minimum and you definitely need to integrate rudder into it and not just while it's knife edge. You will find that to hold a line during a slow roll, you need constantly varying elevator and rudder inputs to not only hold altitude, but to counter each other's effects that individually will take the model off the straight line you want.

So for example, you're rolling right. as the model continues to bank more, you will naturally want to feed in some up elevator, but that is going to start a turn to the right. You have to counteract that by putting in a corresponding left rudder input that increases as the model approaches knife edge, while the up input begins to decrease, becoming zero at knife edge. The same idea applies all around the entire roll; you will have to think ahead to visualize what the required inputs are going to be. This may take a lot of practice!

You can definitely start by getting the basic mechanics down by just assuring that you knock the correct direction of rudder in, even if you see a wobbly result at first. You will at least train yourself and develop some muscle memory so that you don't constantly question yourself about what the basic rudder input is in the knife edge quadrants. Then you start working on the finesse of dialing in more rudder as elevator input increases and decreases as the roll progresses towards 90 degrees and 270 degrees. BTW, it doesn't take a whole lot of rudder/elevator when this is done right and you get them working together effectively to maintain altitude while cancelling each other horizontally.

RE: Rolls How to?
 

It depends on your personal objectives. The roll rate should be whatever you can comfortably stop at the 180 or 360 degree mark. Faster rolls will require less correction of elevator and rudder, slower rolls can be more accurate, but only within your ability to coordinate elevator and rudder.

If you're competing in your first season, my advice would be to use the fastest roll rate you can bring to a quick stop on the half roll or full roll mark, or within a very few degrees of wings perfectly level. That might be about one second for a full roll. You should get by fairly well with just a blip of elevator correction at the half-roll mark--IF your roll rate is not too fast, not too slow. Don't forget, a consistent roll rate depends on a consistent airspeed of your model, so practice your upwind and downwind cruising speeds at a consistent rate, level and diagonal up & down. So much to keep track of! Practice is the only solution. A little advice now and then can help, but only if you practice.

A very good exercise for timing the push-elevator input at the 180 mark is to do linked rolls--two rolls, three rolls, four rolls, as many as you can do, continuous rotation, no pauses, keeping a straight & level track or as close as you can come to it. This will teach you timing, rhythm and how small a blip of elevator it takes to keep you on axis. Also, don't overlook the half roll on reverse Cubans where you catch the tail with a little push elevator when you come inverted, keep that 45 degree upline nice and straight. Then gently release that push to transition into the pulled loop segment.

I remember my coach telling me he would do the linked rolls exercise endlessly at his field, and when his timing was a little off he would find himself doing rolling circles. The peanut gallery would give him plaudits for doing rolling circles, but he said what they didn't know was that the rolling circle stuff was easy, the straight and axial linked rolls were the hard part.

I remember in my first season using rudder correction for half rolls, as in the two of two-point, Cubans, Immelmanns, etc.--opposite rudder rolling from upright, same rudder rolling from inverted. It was easier for me to use just one stroke of rudder input for a half roll, whereas <opposite rudder/push/same rudder/pull> was a bit much for a non-slow roll. There was a period when I was practicing slow rolls where it was easier for me to do an on-axis slow roll than it was to do a standard roll.

RE: Rolls How to?
 

I like to use rudder in mine, even some times not needed I still do because i feel it helps keep the heading of my plane. HEADING IS EVERYTHING IN PATTERN!!!!!!!!!

RE: Rolls How to?
 

Mike a good Masters pilot told me "all rolls are slow rolls, no matter how fast they happen". So maybe master the slowroll and then make it faster and faster.

Hard to believe, but supposedly a slow roll is second nature to the higher classes. I obviously have a lot of fuel to burn.

RE: Rolls How to?
 

Nice thread - thanks guys.

RE: Rolls How to?
 

Mike, I have three suggestions:

1. When trying to learn to use both elevator and rudder start with quick four point rolls, this way you don't have the blending issue. Quick aileron to knife edge, opposite rudder...hold, quick aileron to inverted, down elevator...hold, quick aileron to second knife edge, same rudder as aileron...hold, quick aileron again to upright...done. For me this was the easy way to learn which way to input elevator and rudder. With the slow roll you have the blending issues as NJRCFLYER2 mentioned. Of course, you also need blending with a nice slow four point, but this is not what I'm suggesting to start with.

2. For relatively quick rolls don't start out trying to input both rudder and elevator, just do the pump down, pump up, pump down, pump up routine. Make sure you can mentally handle this and step #1 above before you start trying slower rolls integrating elevator and rudder.

3. If you have a flight simulator this is an excellent skill to practice on the SIM. Fly rolls close to the ground on the SIM so you can see how your inputs are affecting the plane.

Keith B

RE: Rolls How to?
 

Hi,

... I was just up to write my personal experience with this issue , but it is exactly descrieb by KeithB in the last post .... totally agree the best solution for me also ...

Kjell olav

RE: Rolls How to?
 

Ditto what Keith said. That's rolls 101 right there.

oh if you're not used to using rudder on the rolls, prepare to wear out the reset button [8D]

Once it becomes second nature, then it starts to blend from mechanical to "feel", which cleans up EVERYTHING. I'd suggest starting to practice point and slow rolls as soon as you can. it will serve you well in the long run.

Another thing is after you get to say the intermediate level and where you can fly it comfortably, go ahead and start playing with advanced. Always fly a step or 2 over your own class while you're learning. the classes are structured to build on each other, so any weaknesses you have will be magnified. An example: think your lines are straight and your wings are level? Fly P-07 and watch what happens.

Fly it like ya stole it!

-Mike

RE: Rolls How to?
 

Good advice guys -- I just started putting some time in on the Advanced schedule and the triangle rolling loop is a bear with the inverted to inverted roll. I started with a simple medium paced roll with a blip of up at center - looked like you know what. Went with a quick input of same rudder then a little up next and it flowed better( it does feel weird at first), at least the first 1/2 of the roll looks decent now. Maybe by 2008 I have this down :D

maustin

RE: Rolls How to?
 

maustin,

You're doing the correct thing on that inverted to inverted roll with the rudder. Actually you can fly really nice inverted to inverted rolls with rudder only as long as the roll isn't too slow. Once you start flying slower inverted to inverted rolls you will need to integrate the elevator.

Keith B