Too much dihedral?

Fujimo

Active member
So I have been scratch building a dornier libelle seaplane as created by “looping looie”
I wanted to ask what the negatives or complications are for excessive dihedral.
Here is a pic of the wing next to my simple scout wing.
And it really appears to have. A lot of dihedral.
It’s my 13 year olds first sea plane.
He has only flown his trainer the aeroscout 1.1
Even though he flies it really well, we are looking for a good transition into aquatic planes
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Ligbaer

50 Percenter
So I have been scratch building a dornier libelle seaplane as created by “looping looie”
I wanted to ask what the negatives or complications are for excessive dihedral.
Here is a pic of the wing next to my simple scout wing.
And it really appears to have. A lot of dihedral.
It’s my 13 year olds first sea plane.
He has only flown his trainer the aeroscout 1.1
Even though he flies it really well, we are looking for a good transition into aquatic planes View attachment 220293 View attachment 220294 View attachment 220295
I would say if your running it 3 channel give it a go and see if its too wobbly if you running it 4channel like the aeroscout then make the wing flat so the ailerons work.
 

cyclone3350

Master member
As a 3 ch. I'm with @Ligbaer. I did this micro with about that much dihedral. I don't fly it like an R/C as I do it like a free flight & add a little rudder here & there to keep it in my backyard.
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Flightspeed

Convicted Necroposter
That’s a decent amount of it. Should be nice n stable. I built a big twin engine stik out of fb and made the wings perfectly flat. The problem is is that eventually they began to droop and that makes the plane unstable. It was really noticeable to…
 

Scotto

Elite member
Ya I think you would be alright. It wont be very aerobatic but it wasnt going to be anyway. It would still be easy to change now before its all skewered on if you dont like it.
 

Fujimo

Active member
Ya I think you would be alright. It wont be very aerobatic but it wasnt going to be anyway. It would still be easy to change now before its all skewered on if you dont like it.
thats where i am at with it!
i could build a new wing with 1/2 the dihedral!
oh well, another two sheets of foamboard i guess :)

hes not there yet for aerobatics.
he flies well by himself, and loves to do low passes and touch and go's
 

Scotto

Elite member
thats where i am at with it!
i could build a new wing with 1/2 the dihedral!
oh well, another two sheets of foamboard i guess :)

hes not there yet for aerobatics.
he flies well by himself, and loves to do low passes and touch and go's
Well dont scrap it! You could build a low wing plane around it. Or just slit the bottom somewhere and make another bend. It could be a polyhedral thing like this.
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TheFlyingBrit

Legendary member
The dihedral imparts stability and acts to level a 3ch plane following a turn, which is a good thing in most cases. However, from experience if you use too much rudder authority and react too erratic with the rudder stick you can impart Dutch roll into the plane. This is where the plane over corrects itself so that it starts to rock from side to side gradually reducing in amplitude (if you don't react and try to correct it).
This first happened to me while flying the Old Fogey and I wondered what the hell was going on, my first instinct was to try to correct the rolling action with more rudder control. This made the situation worse, until I realised by not touching the rudder it corrected itself eventually.
I reduced the rudder throw for the next flight, added plenty of expo and was less aggressive with the stick, the Dutch roll stopped.
Its the only downside I have come across with having large dihedral, but worth a consideration.

The origin of the name Dutch roll is uncertain. However, it is likely that this term, describing a lateral asymmetric motion of an airplane, was borrowed from a reference to similar-appearing motion in ice skating. In 1916, aeronautical engineer Jerome Clarke Hunsaker published the following quote: "Dutch roll – the third element in the [lateral] motion [of an airplane] is a yawing to the right and left, combined with rolling. The motion is oscillatory of period for 7 to 12 seconds, which may or may not be damped. The analogy to 'Dutch Roll' or 'Outer Edge' in ice skating is obvious. In 1916, Dutch Roll was the term used for skating repetitively to right and left (by analogy to the motion described for the aircraft) on the outer edge of one's skates. By 1916, the term had been imported from skating to aeronautical engineering.