tcraftpo

My Feedback: (7)

What would the affects be if I removed the wing dihedral from a plane I am currently building; it does have aileron control. The plane is a GP .25 size Taylorcraft. Thanks for the info.!

crasherboy

It would be less responsive[as far as turns] to rudder input. If you remove all dihedral it would side slip with rudder unless you fed in aileron with your rudder.
That is the reason trainers have more dihedral than more advanced models,easier to fly by a novice. Full scale have some dihedral,even so the pilot has to do coordinated turns. If full scale had dihedral enough to turn on rudder only it would be a bomb in a cross wind.
If it were mine ,I would leave maybe 2%or3% dihedral in the wings,makes it easier to fly. But a straight wing would do better in a cross wind .

LouW

Unless you plan to do a lot of inverted, and knife edge flight, there would be no significant advantage to a flat wing. For scale like flying as well as appearance, a little dihedral will make it easier to fly and it will look more like the full size airplane.

Rodney

I tend to disagree with some of the above comments. On a high wing plane like the Taylorcraft or a J3Cub, I find they perform best with no dihedral at all, much more responsive to aileron yet you still maintain complete rudder control. You will find they perform more like a real airplane, rudder controls yaw, ailerons control roll , no adverse yaw coupling which you get with dihedral. After years of building and flying models, I always remove all dihedral from the high wing planes unless it is necessary to meet some requirements of scale if you are into scale contests. Low wing planes will sometimes benefit from some dihedral, just keep it to the minimum if you want good acrobatic performance and a minimum of adverse yaw with aileron usage.

TedMo

Basically dihedral is used to increase an aircrafts stability. With that said, removal of that alone will not do very much except make it less apt to recover excessive banks. Overall high wing aircraft are not usually satisfactory for aerobatics since their airfoils, power loading, wing planform, decaloge, etc. are not made for aerobatics but for stability and ease of handling. So what do you hope to achieve?

Rodney

I guess you have never heard of Cole , Clipped Wing Taylorcrafts, The Flying Farmer and a few others. How about the Citabra?
A little study of aeronautics, a little study on yaw, pitch and roll axis might change your mind. Dihedral is simply a way to couple roll and yaw, a factor not desired if you want maneuverability. Yes, for a trainer or beginner flyers, dihedral is nice and will aid the "dumb thumbs" problems.

tcraftpo

My Feedback: (7)

Thanks for all the info guys! I guess it all depends on flying experience level and how comfortable you are at flying. TedMo: Ive just heard of other people that build kits leave out dihedral. I wont have this problem with the TCraft, but ive heard of some guys doing it for transportability of larger airplanes; I guess it makes it easier to make the wings seperable??????? I really dont have a reason to do it, but just wanted to know what would happen if I did; although it would be a little easier joining the wings during construction. Thanks again! Pat

buzzard bait

I think taking out scale dihedral really ruins scale appearance. To me it defeats all the effort - I can build a sport model more easily if I don't care about achieving a scale look in the air.

High wing planes already have a dihedral effect because in a slide or a skid pressure will increase under the wing next to the fuselage on the side that needs to be raised. The little bit of extra dihedral needed to give a scale appearance will probably not even be noticeable in comparison with a flat wing on a high wing configuration.

Jim

da Rock

If the model is of a highwing like a Cub or Taylorcraft, removing that dihedral won't even be noticed by lots of modelers. The higher the wing the more dihedral effect of even a flat wing. There simply is obvious dihedral effect when the wing is obviously a high wing.

Almost all the sticks are highwings. But the "high" really isn't very much. So they don't get as much dihedral effect. Of course, most of them don't have a lot of dihedral in their wings to begin with whatever......

Removing the dihedral in a Cub or Taylorcraft "leaves" all the dihedral effect those highwings get from wing location. So you'll still see some self-righting from those airplanes. So lots of modelers won't feel much has been accomplished. One fun part of our hobby is the ease with which we can experiment. So you got a good chance to do what you are wondering about and find out for yourself.

BTW, some highwings with their dihedral removed will look like they've got anhedral. One bunch I fly with got a dozen VERY cheap trainers and everyone built one. Some took out the dihedral, and one of us (grin) built his wing with anhedral. If the model had been made out of sensible materials and with a decent design, we all might have learned a lot. As it was the suckers were cinderblocks with engines. And the flatwings were often confused with mine. When mine wasn't around, that is.

Jezmo

On my old stick the anhedral really made the knife edge stuff a lot better. If memory serves it was about 1 1/4". I made the mistake of setting my new one up flat and it doesn't knife edge as good with a noticeable tendency to roll out.

buzzard bait

That makes sense. Anhedral offsets the dihedral effect of the high wing position. Conversely, a low wing position creates an anhedral effect which designers normally offset by using dihedral. A straight wing on a low wing plane acts as if it has anhedral. For example, the Contender, which has a straight wing and no dihedral (as originally designed), tends to roll in (upside down) on knife edge, and that's why a recommended mod is to turn up the wing tips to create a dihedral effect to offset the anhedral effect of the low straight wing. Jim

TedMo

Rodney; yep have heard and seen most of those mentioned. don't think that was the point of original question. In my mind I thought his desire was to achieve something by eliminating dihedral. Certainly in those aircraft mentioned there was far more than just eliminating dihedral done???

skyway172

My Feedback: (2)

I can agree dihedral is mainly for positive stability. Whether it's a gust of wind, or an intentional bank, you will bank during flight. The more dihedral your airplane has, the more it will self-correct this bank. This is caused by the lower wing producing more vertical lift. The higher wing still produces vertical lift (less of it), and is now has a horizontal lift component.

That being said, if you're inverted, you will be flying with characteristics of negative dihedral ("anhedral"). The lowered wing will now produce less vertical lift, increasing the direction of bank.