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A dihedral question.

FDS

Well-known member
#2
All the warbirds have some dihedral, enough to help their handling. Generally the larger planes are easier to fly than the small ones, as air doesn’t scale down. A simple gyro based stabiliser will also help if you want a bit more auto level. You can set them up to help a lot or a little on any axis, they come in 3 and 6 axis. Too much dihedral is bad for performance.
The P40 is a good warbird to start on, it’s big and reasonably forgiving. The big Mustang is reputedly ok as well.
Try a Simple Scout, keep the WW1 vibe but get some four channel flying under your belt first?
 

Piotrsko

Well-known member
#3
Dihederal has basically 2 effects: 1, it provides an effective angle of attack change on the outside wing to bank the plane when turning. 2, it lowers the center of weight which makes the plane more stable.

Using rudder on a flat wing just skids sideways and generally won't turn much. Too much decreases aspect ratio, and makes the craft overly sensitive to rudder. Typically if a design asks for say a half inch under the wing tips, an 1/8" increase would not be harmful. Better to put the battery on the outside bottom of the fuselage, but that is an over exaggeration. Warbirds are not noted for being stable, a design choice, however, FT published designs have a lot of problems with stability fixed. When you get to the point that your flying is mostly recharging batteries instead of fixing, then feel free to pick whatever plane you like.
 

BATTLEAXE

Well-known member
#4
Good morning @Michael G. Your question about dihedral is a valid one. As you are flying with the Bi/Tri planes they will be really stable on the roll axis due to having a high wing and a low wing, DR1 with another wing in the middle. The dihedral is nice but it can be a crutch of sorts. I am also new to the hobby, just got into it this spring and I have built a whack load of planes and fly pretty much everyday. I did at one point try the SE5 and found that on its roll axis it was stable that it's pitch axis is squirrelly, especially as a 3 channel RET (rudder/elevator/throttle) set up.

If you do go with the warbird side definitely scale up. Like they said the Scout is a good plane to learn on but if you need the WW2 warbird go with the Spitfire. It will be the easiest plane to handle, has the dihedral you are looking for, and I do suggest you set it up as at least a 3 channel AET (aileron/elevator/throttle) configuration. Learn ailerons on that plane and you will never look back. There are build threads for you to pull references from.
 

Merv

Well-known member
#5
If it just a matter of increasing dihedral, How much dihedral?
How much dihedral is a matter of personal choice. The FT planes all come with a "recommended" dihedral gauge. Lay half of the wing flat on the table and put the dihedral gauge under the other half and glue them together.

My self, I don't like a lot of dihedral, I'll cut the recommended in half or eliminate it all together.
 

PoorManRC

Well-known member
#8
Thanks everyone for the great info. I'll try the spit or the p40 as AET and see how i goes
.... Both of those make pretty decent Bank and Yank Flyers.
Keys to their inherent stability (from Aircraft that were DESIGNED to be slightly UNSTABLE - for quicker maneuverability), are mostly due to fairly large Undercambered Wings and slight increase in Dihedral. (example: David W. gave the Spit about 14 degrees of Dihedral, the 1:1 had 9 degrees). We're not talking about radical Dihedral increases.

Like @FDS said, Larger Airframes are always BETTER. Air doesn't scale down!

Some, like @Merv just eliminate all Dihedral. I'm leaning that way, like @BATTLEAXE . I REDUCE it from the Plans, but rarely go LESS than what the real ones had. (EXCEPT for Mini single Engine Planes, but even then don't go extreme) 😉
The FT Scout is similar, but closer Coupled than the WWII Warbirds.

Like @Piotrsko explained, if you're flying RET - you NEED Dihedral!! Otherwise all you'll have is excessive Yaw, and very little turning.

Mostly summarizing... but how you eventually set your Bird up, will ultimately depend on WHAT your Flying Style is, the Aircraft's size, and overall Airframe Design.

I PROMISE! I'm not trying to confuse you. 😎
When you've made some choice of what exactly you WANT to own, build, fly and crash...
And that's your first question, what Plane(s) do YOU want?
Then WE will be better prepared with more specific information! 👍👍

We will definitely be happy to help!
 

PoorManRC

Well-known member
#10
I would jump in and build a 4 channel. The Scout is good for that as it’s a little bit more docile than the warbirds. You really want ailerons to get the full flight experience from the bigger planes.
Absolutely!! The Scout is an awesome Flyer. Even if it doesn't LOOK like it would be! As a bonus, it even has good "Ground Handling". Especially if you add a Tail Wheel. 😉

When I started, the advice (and assumption) was that 3 Channel was THE way to learn....
Except - you're relying on the AIRCRAFT'S design to give you a coordinated Turn with just the Rudder. Some of them weren't designed well enough! 😖

And I have the additional disadvantage of being a former 1:1 Pilot. Yes, disadvantage!! Because I had to UNlearn some things, and didn't have the seat of the pants feel that I was used to.

But, more on point. Real Aircraft steer, mainly with AILERONS.
The Rudder is mainly for Yaw control, and to sometimes help coordinate a Turn....
Once I changed to 4-Channel, Aileron steering...
It all became WAY more comfortable and natural. 😊

Now I suggest to People starting out, to not WASTE time beginning with RET. Because to move up, you'll need to partially unlearn things that you just started getting comfortable with, to go to 4-Channel!! 😉
 

Piotrsko

Well-known member
#11
<rant on> Ok you young whippersnappers, @PoorManRC included: back a hunnert yar agoo, the radio stuff wasn't as trick as todays hardware. My picture over on the left is what I flew starting out. Really. Radio failure was like EVERY flight.

Ok so what you did back then was have something that would fly pretty much on it's own for a couple of minutes. Yes you can learn on ailerons, but that is gonna mean a flatter wing, ailerons hate dihederal, which means it may not recover by itself, high wing planes like the Cub included. If you have access to quality flying friends who can train you, then by all means fly whatever you want. <rant off>
 

Merv

Well-known member
#12
But, more on point. Real Aircraft steer, mainly with AILERONS.
The Rudder is mainly for Yaw control, and to sometimes help coordinate a Turn....

Now I suggest to People starting out, to not WASTE time beginning with RET. Because to move up, you'll need to partially unlearn things that you just started getting comfortable with, to go to 4-Channel!! 😉
I agree with @PoorManRC, I see no reason for a noob to avoid ailerons. I've taught many noobs to fly with ailerons, just start with lower throws.
 

PoorManRC

Well-known member
#13
@Piotrsko I actually agree with you! On some....
Most WWII Warbirds had Ailerons on a Dihedral Wing. Doesn't have to be flat. 😉

I definitely agree that the first few Aircraft SHOULD have Dihedral. The self correcting properties are nearly essential.

As far as 3 vs 4 Channel... I'd recommend nearly ANY small to mini 3 Channel Plane.
But, for larger Airframes (roughly 900mm or more), 4 Channel is a better way to go.
WHY? Because of the new fangled 2.4GhZ Radios! BTW I'm only JUST getting used to using myself. 😜

One Phrase - Channel Mixing! You could program (OR get a friend who knows what they're doing!), a Channel Mix.
.... If you mix a couple of degrees of Rudder WITH the Ailerons, you've then got automatic coordination.

Meaning, all you do on the Tx, is input some Right Aileron on the Right Stick only - and a little Right Rudder is AUTOMATICALLY added, for a smooth stress free Turn!

Of course, there's other Channel combinations that could be mixed...
On a Twin Engine model, you could mix in a little (or a lot!!) of Differential Thrust, to do the same thing - and not even cut the Rudder Hinge!! 😯

Trust me, I'm NOT saying that the old, big lumbering 3 Channel Bird is going extinct. In fact Kids today are even revisiting 30's and 40's Designs!!

But as much as I hated it at first, the new stuff has really boosted the Hobby! Also made it more affordable for more People.
..... and I DON'T miss turning in my 72MHz Transmitter every time I went to a Field!!! 😃😋

~ and thanks for making me feel YOUNG, even if just for a moment!
 

Bricks

Well-known member
#14
Starting with ailerons after you get the hang of it start using your rudder and learn how to make flat turns, inputting rudder and a little opposite aileron to keep your turn flat and not roll into the turn, learn this and landings get so much easier. When landing correct with the rudder not the aileron's done properly will keep the wings level to the ground, less chance of a stall, and can contribute to slower landing speeds.
 

PoorManRC

Well-known member
#15
@Bricks Thanks. That's a point I forgot....
(HEY, if Flying was easy, everyone would be doing it!!) 😜😆😄

Yes, Landing. A good Landing especially in any Wind, needs practice with using a Rudder! Yaw control is certainly important when coming down.....
Unless you're one of the type that just barrels in at 100mph!! 😄
 
#16
WHOA!! nelly time out.
thanks guys that's all great info but it may as well be in Chinese.
its obvious im not as plane savy as most of you are. I just asked how much dihedral should I add to get that auto level from any of the war birds big/small or what have you. if I cant get the same handling OK no biggie. if I can, how much should I add? 1/2" 1"? because heres my problem I can fly 3-4 channels just fine as long im staring out the front windshield, standing on the ground looking up throws me off. I've played some pretty realistic flight simulators to know that I do better in the cockpit. the mini se5/dr1 make it a little easier to with their auto correct but I dont want to fly the same two planes forever... so how can I fly the war birds without putting a drone camera in the cockpit giving me a live feed to a tv set. or some gyro thingy ma bobber.
 

BATTLEAXE

Well-known member
#17
WHOA!! nelly time out.
thanks guys that's all great info but it may as well be in Chinese.
its obvious im not as plane savy as most of you are. I just asked how much dihedral should I add to get that auto level from any of the war birds big/small or what have you. if I cant get the same handling OK no biggie. if I can, how much should I add? 1/2" 1"? because heres my problem I can fly 3-4 channels just fine as long im staring out the front windshield, standing on the ground looking up throws me off. I've played some pretty realistic flight simulators to know that I do better in the cockpit. the mini se5/dr1 make it a little easier to with their auto correct but I dont want to fly the same two planes forever... so how can I fly the war birds without putting a drone camera in the cockpit giving me a live feed to a tv set. or some gyro thingy ma bobber.
The stock dihedral will do the same as the 2 Mini's your talking about, just the warbirds are faster so it will seem to be less but is not.

Do you have orientation issues when flying towards yourself as compared to away from you? Because if that's the problem dihedral isn't what you need to keep a plane level. Pro tip- It is really easy to tell which direction you need to correct for level when its flying away from you right, like you are in the cockpit flying it yourself. It tips right and you move left. When its flying towards you and you need to level out, point your stick at the low wing tip and it will level off. Plane is dropping the wing tip on your right, move the stick to the right. Just a visual reference for you to try.
 
#18
The stock dihedral will do the same as the 2 Mini's your talking about, just the warbirds are faster so it will seem to be less but is not.

Do you have orientation issues when flying towards yourself as compared to away from you? Because if that's the problem dihedral isn't what you need to keep a plane level. Pro tip- It is really easy to tell which direction you need to correct for level when its flying away from you right, like you are in the cockpit flying it yourself. It tips right and you move left. When its flying towards you and you need to level out, point your stick at the low wing tip and it will level off. Plane is dropping the wing tip on your right, move the stick to the right. Just a visual reference for you to try.
The stock dihedral will do the same as the 2 Mini's your talking about, just the warbirds are faster so it will seem to be less but is not.

Do you have orientation issues when flying towards yourself as compared to away from you? Because if that's the problem dihedral isn't what you need to keep a plane level. Pro tip- It is really easy to tell which direction you need to correct for level when its flying away from you right, like you are in the cockpit flying it yourself. It tips right and you move left. When its flying towards you and you need to level out, point your stick at the low wing tip and it will level off. Plane is dropping the wing tip on your right, move the stick to the right. Just a visual reference for you to try.[/QUOTE. I have a little orientation problem I just have a problem telling if the plane is level coming out of a turn. I can tell if it's coming straight at me or heading away the problem is flying across the front me left to right and Right to left.
 
#19
When we drive our cars we sit in the driver's seat none of us have a full size r/c car. We get a better perspective behind the wheel. Looking out the windshield of a plane gives me a better perspective of level, pitch, banking, rolling you get the picture, I can fly an r/c plane straight through my car port as long as I'm looking out the windshield. Standing on the ground I get none of that perspective. The mini se5/dr1 take a lot of the guess work out, all I do is let go of the stick and they come out of the turn smooth as glass. I don't want to have to stick a camera in every plane I build because all I'm doing is turning this into just another simulator. I want to actually see the plane from the outside. Now if the stock dihedral gives me the same effect I'll give it a shot.
 

BATTLEAXE

Well-known member
#20
When we drive our cars we sit in the driver's seat none of us have a full size r/c car. We get a better perspective behind the wheel. Looking out the windshield of a plane gives me a better perspective of level, pitch, banking, rolling you get the picture, I can fly an r/c plane straight through my car port as long as I'm looking out the windshield. Standing on the ground I get none of that perspective. The mini se5/dr1 take a lot of the guess work out, all I do is let go of the stick and they come out of the turn smooth as glass. I don't want to have to stick a camera in every plane I build because all I'm doing is turning this into just another simulator. I want to actually see the plane from the outside. Now if the stock dihedral gives me the same effect I'll give it a shot.
Go with the stock dihedral and if it works, great. If not, it's just foamboard, build a new one with more dihedral. A lot of what we do and why we enjoy the FT designs and mediums is its cheap to build, crash, and repeat. The more you fly, the more you crash, the more you learn. Soon perspective will become intuitive and you won't even worry about dihedral. Its just hand/eye coordination and muscle memory just like everything else. Have fun and good luck.