Eindecker Design Update

My original thought with this design was to use a flat bottom wing with a 1 1/2" wing-tube.
This works fine but I had wanted the wing wires to be non functional. Without any sheeting on the wing there is just to much twist without functional wing wires.
Also the wing tips are not strong enough when a cross wind picks up one side and drives the other tip along the ground.

So a redesign has been done.

1. The new wing is the same overall size.
2. The airfoil has been changed to an under cambered airfoil.
3. 1" wing tube for ease of assembly.
4, Ailerons moved inboard one bay, 5 bays wide and 4" deep instead of 6" deep.
5. One piece wing tip braced back into the wing two ribs.
6. Wing wires are required.

I have completed the drawings for these changes and I have cut the left wing panel.
The new wing build begins today.

Larry

There certainly is a lot[X(] going inside the Eindecker wing, that's for sure! It is indeed and interesting plane to model.

Yes Jim we flew it again............[&o][&o]
This time it flew very well! I have a 12 minute go pro on board video and I have a full on the ground video...........still working on up loading[:@][:@]

I balanced the plane at your recommended 25% and I felt it was to sluggish on the controls and dropped some nose weight and was ready to take another flight when I noticed the electronic ignition pick-up screws fell out!..........that ended the day............[]

I feel very good about next weekend. I am hoping to get in more than 1 flight per day! LOL!

I am telling you Jim...the pressure that ART and LARRY put on you when you are flying...is incredable!
I can tell they are rolling there eyes behind my back....I can hear Art mumbling "he hasent flow straight and level flight yet!"
I'm just kidding ..........about Larry...............

Hope to see you at least one of our camp-in flys.............


HPA

Here is the new wing tip dry fitted together. The tip is one piece 1/8" Baltic Birch and I score the front where it curves the most with the laser.
There are tabs that slot into the double tip rib. The brace pieces in the rear are 1" wide Baltic Birch glued on the top and bottom of the tip that are tied back into rib 13.

Larry

I don't have enough glue left to build two more wing panels[X(]......so I guess I will have to plod along with the Mark I Mod II version of the wing panels.

I like what you have done, Larry. I think this is a nice improvement as well as being a closer to scale under cambered airfoil.

Turtle Report

The second wing tip has been fitted and glued up. The aileron has been cut down to size. After the glue dries on the tip I can clean up the edges and fit the re-sized aileron.

I did some more measuring and I calculate the new aileron area is approximately 6% of the total wing area. I don't think this will be noticeably different in roll response than what Paul's plane is....his aileron area is about 33% greater than mine and looks to be 8% or so.
It will be fun to compare the two planes and make in the field evaluations of each one and then compare them to Larry's version.

They all will exhibit adequate roll control and be much snappier than a wing warp system would.

(waiting on glue to dry)
Art

Larry, I'm so glad to see that you have redesigned the wing!!! This is the much more scale wing that your model truly deserves and I think you'll find that it will appeal to many future customers. And your design thinking is right on the money; if the model needs functional rigging (and really what 1/3 scale WWI model doesn't?) then you might as well have a scale wing!

VERY WELL DONE!!!

Larry, one question: Will you need to be altering the angle of attack?

Art, beg, borrow, or steal more glue!!! At the very least, make plans now for being able to fit a pair of the Mark II wings later. On the Snipe prototype, I built the rudder three times.

Art,

I buy glue by the gallon.

Abu,

With this design I placed the wing tube back 6 3/4" from the leading edge which is just less than 30% of the cord.
The tube can now be used as a lifting point for balancing.

I am going to set the anti rotation pins for 3 degrees of incidence.

Larry

I hear ya, Don. But after all this model has a rudder, elevators and ailerons - I don't think I'm gonna miss an under cambered airfoil.

I promise on my next Eindecker build I will use wing warping, full flying tail surfaces and functioning scale gear[8D].......I just don't quite know when that will be.

That's a thought.

Turtle report:

Got the second aileron end rib glued in - tomorrow, after the glues dries I will put the cap strips on.

The wing looks much nicer at the tip with a one piece wing tip and recessed aileron.

That's all folks! (for tonight anyway)

Signed
The Turtle

It isn't just the undercambered airfoil. This new wing changes the whole look of the model. Also while it's simple to replace the kit's rudder and stab with full-flying version, there would have been no way to modify the Mark I wing.

I really can't disagree with what you are saying, but my main goal for this airplane is to fly, fly, fly! And I can do that with either wing.

I like the looks of the undercambered wing much better![8D] I was thinking...If you hinged the ailerons at the top and covered over the gap with the covering, the ailerons wouldn't be so noticable and it might look more realistic. Anyway, all my 1/3 scale planes have thin airfoils and functional flying wires and it has never been a problem.

Jim

The small 1/6 scale EIII from AerodromeRC uses a thin full-span barn-door type aileron hinged with fabric at the top. So the effect looks very much like wing warping. BTW, a clubmate came up with a very inventive solution on this own-designed sport-scale EIII. He had servos in the fuselage that actually rotated the two wing panels in opposite directions! I'm not recommending this, especially not for a 1/3 scale model, but it just goes to show there are many ways to skin a cat.

BTW, some modelers might make the mistake of thinking of the EIII as a "small" aircraft because it only had one wing. But the fact of the matter is that it had a wingspan of 10m, compared with only 8m for a Sopwith Pup. In fact, the EIII's wingspan was a large as the 2-seat Sopwith 1 1/2 Strutter!

So at 1/3 scale, this is no teeny model (as we can see from the photo of Paul lifting it out of his truck)!!! Can you imagine trying to make a 1/3 scale Strutter without functional rigging! [X(]

Soon.................very soon..........................[8D]


HPA

Here is the new wing all laid out. I have made jigs for the rib placement and end pieces to keep things aligned.
At this point everything is locked into place with no glue.

I plan on using the small bottle pictured with wood glue to glue things together. I get these bottles at my local wood worker supply store.

I am doing it this way since all of the ribs slide onto the 1/4"x3/4" spars and it would be impossible to glue pieces in place as you build and keep things straight.

Larry

Larry

Nicely done! This is making me want the new version wing........do you think you might be putting out an ARC version of the new modification?

(or in case that wasn't a strong enough hint - when will you get mine built?) hahahahaahhah

Are you telling me that the little squirt bottle is what you will use to apply all the glue? Does it work very well?

Later
Art

Art,

The little bottle didn't work. The glue was just too thick.
I ended up using little sticks and q-tips to spread the glue around.

Remember this is my third set of wings, Paul's wings, a just built completed set with the flat bottom wing and these.

No more Eindecker wing building for me.
I need to get my plane finished for Mint Julep!

I got most of the left wing glued together tonight and I should finish it off tomorrow evening.
I would like to have the right panel and a new stab finished by Sunday evening.

I also have made some revisions to the stab with a 3/8"x3/8" stock leading edge.
For production kits I am going to use the strut like Paul added to his stab and have that tied back into the struts for the tail skid.

Larry

Larry,
Barry and I use that little bottle all the time!
The trick is to thin the glue alittle with some H2O and it will work like a champ!

HPA

That is the design for wing tips I use on most of my projects . I cut the inside of the sheeting back to lighten the tips of the win , it is still strong , plus you can contour the top of the wing rib to match airfoil all the way to the wing tip .. Very Nice on the improvement !

Turtle Report

I haven't got a lot accomplished this past week as I have been under the weather and going to work was about all I could get done......gotta keep the paycheck coming.

Starting to work on the elevators......... I traced the outline of the original elevators onto 1/8 balsa sheet.......found some 3/8" balsa sticks......the outline will be double pieces and the ribs will be single pieces.......then the top sheet will go on.

I will cut the control horns from 1/8" a/c ply and add them after the elevators are covered.

Ohio State is about to tip off and IU is coming up at 2:45 - so I won't get much done today either [8D]