obrien135

Do you have to give a plane right rudder to make a left banking turn and left rudder when making a right turn or do you just use up elevator to keep it from going into a dive?

Top_Gunn

My Feedback: (6)

Up elevator. Sometimes a little left rudder will help, too. Do not use right rudder when making a left turn.

Hydro Junkie

What the rudder does, when used in a turn, is not what common sense says it does. Turn the front tires on a car, that vehicle changes direction. In the case of an airplane, however, it's the ailerons that actually turn the plane by changing the direction of lift. The problem comes in with the drag added by using the ailerons. An aileron that goes up adds little drag since it's partially masked by the thickness of the wing and the higher speed of the air over the top of the wing. An aileron that goes down, on the other hand, adds a considerable amount of drag since it drops further into the air flow under the wing. Since the aileron that drops is on the outside of the turn, the plane will try to turn in the opposite direction due to the drag. The rudder is used to offset that "inverse" drag to "help" the plane turn in the desired direction. To use the rudder alone, to try to change the plane's direction, will result in the plane sliding sideways through the air like a car trying to turn on a slick road

Hydro Junkie

Maybe with pattern planes but many R/C planes behave just like full sized planes, in just the way I described. In fact, some full sized planes have the rudder and ailerons "coupled" to lower the work load on the pilot, including some Piper and Cessna models. You move the yoke/stick, the rudder moved along with the ailerons though, if desired, the pilot could override the coupling manually using the rudder pedals at the same time as the stick/yoke

j.duncker

My Feedback: (2)

I am going to disagree with one of my learned friends above.

It is perfectly possible to make turns with a rudder providing the wing has dihedral.

Many of us old timers started flying radio control with only one channel and that was rudder.

This is one of the most well known small [ almost indestructible ] one channel models the Sharkface designed by Eric Clutton.

There has been a resurgence of interest in flying rudder only models in the UK with the availability of reliable single channel outfits using a single modern servo which mimics the control we had.

I flew my Sharkface with a sequential escapement powered by a long rubber band which had to be wound before ever flight. If the last press was right rudder the next press was left then the next press was right.

Hydro Junkie

I hope you're not referring to me as my first plane was a Kadet Jr. It was a rudder/elevator/throttle aircraft, with a significant amount of dihedral, 2+ inches of it. In fact, the instructions said to hook the rudder servo to the aileron output on the receiver to teach new pilots to use that channel to turn the plane. IF that is what they were trying to teach new pilots back then, it seems to me that my post about how planes turn is right on target, both in R/C and full sized flying

Hydro Junkie

Go back and read my last post. Better yet, I'll just post it again. The Sig three channel trainers teach new pilots to use the right stick to change attitude and direction. That set up is right in the building and set up manual. It doesn't say to use the rudder on the left stick, it says to use it on the aileron channel, meaning the right stick. That being the case, it does point to using ailerons to turn rather than the rudder. It also has the side affect of not teaching new pilots how to use the rudder. If you look at the full size Boeing 727 and 747, they only use a third of their rudder surface area in flight. Unless the plane has issues controlling yaw, the upper 2/3rds of the rudder is basically locked in place. The bottom third is only used to keep the plane from sliding during a turn, something that would be shown by the turn and bank indicator on the dashboard.

Hydro Junkie

Not misleading at all. I'm quoting an R/C trainer's build manual and known operation of several full sized aircraft. Since you fly pattern planes, as you noted when you posted "The Modern crop of pattern airplanes will do a turn or even 360 degree circles using rudder input only with no bank angle", which obviously handle different than a trainer, a Piper or Cessna, I can only assume your knowledge of aeronautical principles is limited to how the R/C planes that you've flown react to control inputs and not accepted ones used in general aviation and three channel trainers

Hydro Junkie

I'll tell you what, you can argue with NASA as I'm done with this thread:
https://www.grc.nasa.gov/www/k-12/airplane/turns.html

jaka

Hi!
You turn a high or low winged aileron R/C type model by giving aileron and then elevator! No rudder is needed! -Well, for a big 1/4 scale CUB rudder is needed.

j.duncker

My Feedback: (2)

Since this the beginners forum I think I should warn beginners that your typical trainer will not do knife edge loops. If you have moved on to something a bit sportier it may do a knife edge loop but try the first ones at least 3 mistakes high.

If you have a total hooligan machine like this Morris Hobbies Sledge of mine then it will do vertical knife edge figure of 8s, fly control line circuits with no banking at all and at times totally confound the laws of aerodynamics.

Hydro Junkie

Just couldn't leave me out of the conversation, could you Speed. As I said in my last two posts, I was quoting a NASA document that I even posted a link to and the construction manual for a Sig Kadet JR. If you all still want to argue about everything, argue with Sig and NASA and leave me out of it

RCKen

My Feedback: (9)

When you were growing up and during the day you did something wrong and your mom would say "You just wait until your father gets home"? And then when your dad got home it was like the end of the world for you because he won't put up with anything you did.

Well guess what??? Dad is here, and he's not happy with what is going on here in this thread, this sub-forum, and this website/online community. And I'm pretty upset with the 2 members causing all the problems.

If you look back through this thread you will see a lot of posts that have been removed. That is because there were 2 members that were bashing each other in this thread. They have been removed because the attacks these member were doing to each other takes away from the beginner that was trying to get some help in learning to fly. These members may have thought that they were helping new flyer, but what they don't realize that they are actually doing the new flyer no service at all and are probably causing more problems for the new pilot. But I can tell you this, it is going to stop right here and right now. If those involved continue to fight with each other you will first find your ability to post on RCU to be throttled down to the point that we will approve or disapprove any post you make. And if you can't reform yourself then you find that you are on the outside of RCU looking in. I will say that you had better not try my patience here as I will not hesitate if you can't learn to get along with each other. And that isn't limited to the Beginners forum, that includes all of RCU.

Now one last point that I want to clarify here. One person has stated that they have freedom of speech and that gives them the ability to post what they like. I want you to see one part of the RCU Community Rules and what it says on this mattterEvery member agrees to follow these RCU guidelines when they join RCU.

I am sorry that other have had to see this, but that is the problems have to be settled

Ken

speedracerntrixie

My Feedback: (29)

jester_s1

I'm going to take exception with that statement, speedracerntrixie. While you are very knowledgeable and a true asset on this forum, others have every but as much right to disagree with you as you have to post. It's true that personal attacks and general rudeness aren't allowed on the forum. But neither is baiting, trolling, or otherwise posting things that you know are going to get a rise out of the other guy.
We'd all do well to use our freedom of speech to teach new pilots and generally contribute to the wealth of knowledge that exists in this forum. Bickering is beneath all of us.

pmcafee

No, you don't have to use rudder. Be especially careful when turning while setting up to land. You're on the downwind leg and turning on to final. Try to keep the bank fairly shallow and maintain your airspeed. Too steep of a bank at a low airspeed could cause the aircraft to tip stall. That would most likely result in a crash. The rudder should come into play when you're lining up to land to maintain your heading.

watdazit

I am not about to disagree with any of the previous answers, but to simply answer the original question about giving opposite rudder I would say no, unless you are banking hard and slow and you can catch the plane if something unexpected happens, like heading for the deck.. Opposite rudder on these occasions can act as an elevator and keeps the nose up. If the nose drops on a steep bank the wrong reaction would be to give more up elevator.. This will not raise the nose but may cause the plane to roll over on it's back and head for the deck. I often think I should really understand the dynamics of this problem but at my age I like to think of other things, like a juicy steak. Think of knife edge flying where the rudder is used as an elevator. Some planes benefit from a slight amount of right rudder with right aileron and vice versa. I am only talking a few degrees mixed in. Try flying straight and level with any plane and try steering with the rudder. You will see various planes will have varying amounts of turn. My first instructor used to go spare with me if I banked over 30 degrees. He always said as a learner it was a recipe for tears.

Appowner

To answer your original question, Maybe! Since all models are anything but created equal.

The thing is between incidence angles, dihedral, control throws, CG and so on. There are so many variables that can affect whether or not one would use, in your case rudder, during a turn. You can have two J-3 Cubs. The only difference is the afore mentioned variables. One flies great, like a Cub should (with rudder). And the other is a rocket requiring little if any rudder. Or aileron. Or elevator. Or...

So the thing to do is, if you're not up to it then have someone else test fly the model for you. Have them put it through its paces and tell you what controls they find they need in various situations. Then you take over and start learning how to fly that particular model.

You need to know what the model can do.
How to go about doing it.
Then practice, practice and more practice.

Top_Gunn

My Feedback: (6)

There are certainly airplanes that benefit from some use of rudder in normal turns. But his question was whether he should use right rudder while making left turns and vice versa. There are You-Tube videos out there that tell people to do just that, apparently based on some notion that skidding turns are better than co-ordinated ones. That is not good advice for a beginner.

Hydro Junkie

The problem with You-Tube videos is that anyone can make and post them. Having a true knowledge on the subject is just a bonus, not a requirement. I've seen several videos that had to come from someone that had no clue as to the subject they were posting about yet, in the comments area, there was dozens of comments thanking the unknowing poster over something in the video. The really bad part was that those who called the poster out for being wrong were, more or less, attacked by those that thought the poster was the greatest thing since sliced bread. Oh well, I guess if it's found on the internet, it has to be true these days

Appowner

And my point is that even two seemingly identical planes can have vastly different flight characteristics. So what you would do for one you may not do for the other. Something we can't determine from behind our keyboards. And that he needs to get to know his particular plane. With the help of someone more skilled if necessary.

I see way too many both here and the flying field who really have no clue to what they are doing. Many do not know how to fly let alone build or repair a model. They simply manage to not crash, most the time. Probably due in part to some computer game. One poster salvaged the electronics from a foamy and wanted to build an airboat. But was confused when he reversed the prop (to make it a pusher) and yet it blew the same direction as before.

Let's not tell them if they do or do not need rudder for their particular application. Let's tell them how to go about learning how to really fly what they have. So maybe they don't get discouraged and leave the hobby.

speedracerntrixie

My Feedback: (29)

Top_Gunn

My Feedback: (6)

Have you ever flown a model that needed opposite rudder to turn? I'm reasonably sure that any beginner's model that needs that combination is so badly set up (as Speed points out) that a beginner shouldn't be learning to fly with it. The OP is a beginner and seems pretty clearly to have no idea of what normal flying requires. An answer that basically says "all planes are different so we can't answer your question" isn't likely to help him. Every four-channel trainer I know of will turn reasonably well with ailerons (and some elevator). Many of them will turn even better with some rudder in the same direction as the bank, especially if they don't have aileron differential or if they have too much dihedral.

You are absolutely right in saying that he needs the help of someone more skilled; we can't teach him to fly here. But we can disabuse him of the idea he seems to have picked up somewhere that cross-controlled turns are the norm.

Appowner

My question would be, How far over is he banking it? Think knife edge. Is he banking it so far that he's really doing something more akin to a knife edge? All be it a poor one. Which is another reason why he needs to have someone experienced flight test his model.

Top_Gunn

My Feedback: (6)

His question was "Do you have to give a plane right rudder to make a left banking turn ...?" The sensible answer to that question is "No." I'll concede that opposite rudder can sometimes help in a knife-edge or near-knife-edge turn, but if that's what a beginner is doing the best advice is "Don't bank that much." When beginners make turns that steep, they usually turn into an unintentional split-S, followed by a crash unless they're on a trainer cord.

He certainly does need in-person help from an experienced flier. I have known people who have taught themselves to fly, though they tend to go through several models on the way.