Question about round loops

Last weekend I flew at the Ron Connors Memorial contest. In the weeks leading up to the contest I practiced my inside loops and I thought I had them figured out. When I asked one of the judges for critique of my flight, among other things, he mentioned that my loops looked like vertial eggs and that he's seen me fly MUCH better loops with my other plane. Both planes were properly trimmed. No major warps on either plane as well.

My question is: Is it possible for two planes to fly different rounds even though I fly them the same way? The way I fly the loops is set the turn rate at the onset of the first loop and keep it the same through the entire maneuver.

P.S. This was the first contest I entered in Advanced. I am very excited about this new challenge! Now if only I could build a 20 pointer plane....

>Last weekend I flew at the Ron Connors Memorial contest. In
>the weeks leading up to the contest I practiced my inside
>loops and I thought I had them figured out. When I asked one
>of the judges for critique of my flight, among other things,
>he mentioned that my loops looked like vertial eggs and that
>he's seen me fly MUCH better loops with my other plane. Both
>planes were properly trimmed. No major warps on either plane
>as well.
>
>My question is: Is it possible for two planes to fly
>different rounds even though I fly them the same way? The
>way I fly the loops is set the turn rate at the onset of the
>first loop and keep it the same through the entire maneuver.
>
>P.S. This was the first contest I entered in Advanced. I am
>very excited about this new challenge! Now if only I could
>build a 20 pointer plane....
>
>Steven Yampolsky
>Webmaster for www.control-line.org

I will make two comments:

"Yes" and

Two planes can definitely fly differently, and if you are setting your turn rate at the outset and merely hold it, the loops will not be round. You must fly through each maneuver--loops included. Many planes climb slower, and dive faster, although it is possible for an engine to kick in and take off in the climb as well. But it is not engine speed that needs to be consistent. It is airplane speed that we strive to keep consistent. If it is not--and for most it is not--then we need to vary the input throughout the loop.

One tip that we received from Ted Fancher that really rang a bell was to strive for a "positive entry" to the loops (eights, etc.) Many pilots enter the loops with sort of a "lazy" turn of the hand in entering the first loop. The result is the plane will climb higher and you will either end up with a larger first loop or egg shaped loops all the way. You need to snap your hand to the degree (and only to the degree) of input you need to fly the loop. Do the same at the intersection of the eights. Snap the hand from "up" to "down" (or "down" to "up") but just to the degree needed, so the airplane begins immediately to track in the direction you want it to fly. But from that point on you need to fly the plane through the loops, constantly applying minor corrections to keep it on track of a perfect round. Don't make fast hard corrections here or your loops will get "lumpy" (an expression first herd from Howard Rush).

OK, that maneuver is now perfect. Next.

Steve....
Len's input, especially as suggested by Ted, is probably valid.

When I read your post, I was going to suggest that the reason for the comment was that the judges were tall and narrow minded.

See Ya

If you hit the control and then hold it, you will get an egg. The airplane will start climbing, the airspeed will go down, the force on the tailplane from the prop blast remains the same so you have an initiall gentle climb followed by a tighter circle followed by a widening turn on the downside as the airspeed increases. This is more typically seen in RC where so many first timers jsut pull the stick all the way back on their trainer. One of your planes probably doesn't bleed as much speed as the other, so the loops are rounder.

So Enter your loop, then adjust your controls apporpriatly to get the manuever round. Hopefully you won't have to lean down into it at the top to keep the loop round, but that would be an extreme example for examples sake.

>way back on their trainer. One of your planes probably
>doesn't bleed as much speed as the other, so the loops are
>rounder.

You know, this could explain it! My current plane does bleed the speed VERY easily! I just didn't put two and two together!

I though that if the plane bleeds the speed easily, it will only manifest itself in hard corners like squares, triangles, hourglass, etc...

>When I read your post, I was going to suggest that the
>reason for the comment was that the judges were tall and
>narrow minded.
I have COMPLETE confidence in the judges expertise. His advice always worked for me! I am positive it is either me or the plane.

>One tip that we received from Ted Fancher that really rang a
>bell was to strive for a "positive entry" to the loops
>(eights, etc.) Many pilots enter the loops with sort of a
>"lazy" turn of the hand in entering the first loop. The

The way I interpreted his suggestions is that I have to establish a positive turn rate and just keep it through the maneuver. I practiced his suggestion on my old plane and it worked like a charm. With my current plane, I get an egg.

>OK, that maneuver is now perfect. Next.
How about flat bottoms and not crashing....

>Last weekend I flew at the Ron Connors Memorial contest. In
>the weeks leading up to the contest I practiced my inside
>loops and I thought I had them figured out. When I asked one
>of the judges for critique of my flight, among other things,
>he mentioned that my loops looked like vertial eggs and that
>he's seen me fly MUCH better loops with my other plane. Both
>planes were properly trimmed. No major warps on either plane
>as well.
>
>My question is: Is it possible for two planes to fly
>different rounds even though I fly them the same way? The
>way I fly the loops is set the turn rate at the onset of the
>first loop and keep it the same through the entire maneuver.
>
>P.S. This was the first contest I entered in Advanced. I am
>very excited about this new challenge! Now if only I could
>build a 20 pointer plane....
>
Steve,
Performing "Round" loops is critical to good scores in P/A. When you consider that many of the maneuvers in the pattern are made up of rounds, it makes since to make sure the model flies a round loop to start with. Model trim is always a factor but it may be the way you are flying the loops that is the problem or a combination of both.

First lets talk about trimming the model for better loops. It has been my experience that a slightly nose heavy model performs loops better than a tail-heavy model so try adding a small amount of nose weight and see if that helps. Also make sure the line tension of the model is equal at the bottom and at the top of the loop as possible. In addition, if the model has too much or too little tip weight can effect the loop tracking. So use a "sharp eye" from a friend to watch the model fly a series of inside and outside loops. Look for any signs of model yawing or rolling and pay close attention to see if the wing stays parallel to the lines. Too much tip weight will cause the wing to fly out or tilt to the outside of the loop.

Now lets talk about flying the loop. Setting the handle in one position and allowing the model to track through the loop will not work. The control input is always changing slightly from beginning to end. You have to see the round in your mind's eye and follow that path. Egg shaped loops (point on the bottom) is most likely trying too hard to hit the bottoms and not allowing the model to track smoothly through the 4 ' to 6' bottom.

This may or may not be a problem but the position of your hand during the loop is worth considering (it was for me). The handle must be vertical and not tilted to one side or the other. In addition, I found it much easier with my hand and handle elevated to almost face level so I could sort of sight down the lines. This allowed a broader overall view of the loop (and most of the other maneuvers) and a better perspective.

I hope this helps and I am sure other people will post additional hints that may help.

There is another thought I should have added, which also works as a follow-up to Mikey. Make sure your hand is aimed at the model and that the hand tracks the path of the model. In other words, do not hold the handle still while you fly the maneuver, but follow the path of the maneuver with the hand. And make sure it is elevated so the lines go straight out from the hand (and arm). If you hold it down too low (or up to high) you put an automatic bias in the handle from the get go. Not good.

> So use a "sharp eye" from a
>friend to watch the model fly a series of inside and outside
>loops. Look for any signs of model yawing or rolling and
>pay close attention to see if the wing stays parallel to the
>lines. Too much tip weight will cause the wing to fly out
>or tilt to the outside of the loop.

Hmm.. I haven't thought of that! I'll check it out!

>Setting the handle in
>one position and allowing the model to track through the
>loop will not work.
Agreed. I usually set the turn and the just "scribe" the circle with my hand.

>This may or may not be a problem but the position of your
>hand during the loop is worth considering (it was for me).
>The handle must be vertical and not tilted to one side or
>the other.
I usually fly with my hand at 11 o'clock position for the level flight and 12 o'clock for inverted. Either way, both loops are egg shaped.

I am a long way from making perfect ROUND loops myself but I am getting much better. I have noticed if I pull up to do a loop then follow the airplane through the loop with my arm like aiming a rifle barrel at the airplane all the time as it goes through the loop the loop is round as long as I don't move my wrist. If I pull up then stand there like a plastic mannequin the loops look like eggs. I am not sure this is the best way to do it or not. I fly by myself and have to lean without any help so maybe there is a better way.

I agree with Gary, you gotta get the body moving! For me, the arm has to follow through the loop to get them looking round.

I was watching the expert pilots this weekend at Huntersville, and the pro's have body movement.

From my prespective..

You must fly the airplane through every inch of the consecutive loops. Not only must they be perfectly round, they must track directly on top of each other. Not an easy feat if you know what I mean. Then you must line them up exactly with correct intersections in the eights and fourleaf. Do a lot of work in these manuvers and watch you scores improve a lot. Of course my flying at huntersville was pretty ugly with a model with a different engine and not completely trimmed. Ugh. so much to do so little time!!

Steven,

You've been given the basics, but you still need to be very critical of what you're doing, and you most certainly need to watch some highly-skilled fliers.

As I believe you will be in Muncie soon, my suggestion is to watch--maybe even video tape--Paul Walker. I can't believe others who have seen him fly missed this, but it appears as if PW cranks in quite a lot of control in changing direction of model into a round, whereupon he almost immediately backs it off to the amount of control needed to at least continue the loop, further hand/arm movements being a bit too subtle to easily pick up from outside the circle.

The rationale, as stated to me once, was that easing into the loop is not a good thing, this also mentioned in thread. For whatever reason, PW has learned to make the transition from level flight to a round noticeable in the quick response of the model, the predictability of first loop and those following.

Another technique is to pick a spot in the sky, ideally the center of your loop. Focus on this spot. Fly the model with your peripheral vision. You may well be shocked at seeing how far out of round your loops really are. Think well of me even when you're kicking yourself all over the field. You're on the road to getting better...

Yup, Its called tracing the maneuver, and you can practise this without flying....

I remember watching Casale fly loops at the Team Trials one year (first time I'd ever watched good stunt flying). He was in some sort of crouch, knees bent, and his whole body moved around in a circle, with the knees doing the moving. Hard to describe. It did look funny at the time. Sort of like a Toreador move.

Steve,

Thanks for asking this question. I have already learned a few things to try from the replies posted here.

One of Mike Pratt's suggestions hit very close to home: last week I changed from a plastic spinner to a metal spinner in order to shift the CG forward. The performance was much better all around - line tension and turn.

I had one other model that had tail weight added so it would balance at the published CG. I have now learned that for my flying style, the published CG is not the best balance point for this model. The tail weight has gradually come off and the model's performance has improved with each iteration.

Little things can help a lot. Your results may vary.

Ron,

The engine now is at Rich's getting a new front seal and possibly front bearings. It should be back by about Tuesday or Wendsday.

Don't know why I had to tell you that, but I did anyway.

Yikes, what happened? It was running so well for me.

If you don't want it, just give it back. No harm - no foul. I'll give Richard a call and have him ship it to me.

Give me a call at home. The number is on the club roster. I'm on vacation all week, so I can learn to fly before heading up to Brodak's.

That is typically problem of inconsistent feedback to the handle (well if you are sure you do not do it by your hand … but if you say it is problem of that ONE model the I think yes). Probably because of wrong position of leadouts. But could be also engine run, rudder, tip weight or if not the same inside and outside then flaps misalignment. Inconsistent feedback (or line tension) leads to opening or tightening at constant hand input.

Steve: Are ya confused yet?

>Steve: Are ya confused yet?

Yes but that's nothing new. You know I'll be bugging you for an explanation shortly!