Calling all wing warpers!!

Breguet · 30 August 2006, 09:27 PM

I would be interested to hear of peoples experiences in this regard. You hear all sorts of stories but actual experience is another thing. I have built a Balsa USA (40size) EIII and have made the wing warping work (I get about 3/8" movement at each tip) but wonder how it will go.

Comments?

AeroClassics · 31 August 2006, 10:47 AM

Quote:

Originally Posted by Breguet

I would be interested to hear of peoples experiences in this regard. You hear all sorts of stories but actual experience is another thing. I have built a Balsa USA (40size) EIII and have made the wing warping work (I get about 3/8" movement at each tip) but wonder how it will go.

Comments?

No actual experience yet. But I have a set of 1/4 plans and laser cut parts for an E-III from Bob Holman that I hope to be starting soon. It is not something you see very often at the flying field. More work than most folks want to put into a Sunday flyer, I think.

Doug

PfalzPflyer · 1 September 2006, 07:26 AM

I was just at the Hoosier Dawn Patrol in Muncie, Indiana last month. Art Shelton had a 1/3 scale Fokker Eindecker E1 there that used wing-warping for lateral control.

Even though it was a bit windy that weekend, the E1 flew well. Part of that was undoubtedly due to the skill of Art as a pilot. In fact, several times he was heard to express his admiration of (and desire for!) ailerons.

Sure looked cool, though.

Dean

PfalzPflyer · 1 September 2006, 07:31 AM

Here's a link to a website for video of the Hoosier Dawn Patrol 2006. Lots of great video there, including some of Art Shelton with his 1/3 scale Fokker E1.

http://www.indyflyer.com/dawn/dawn2006.htm

It was a great event. If you were there, you know what I mean. If you missed it - you really missed it!

Dean

WinterHawke · 1 September 2006, 09:36 AM

Dean,

Agree completely - Art's Eindekker flew very well all weekend, and was a joy to watch. He's obviously got a very good handle on wing warping R/C models.

Breguet,

Probably one of the key things to remember with wing warping is that it is NOT going to be effective at slow speeds / high angle of attack. An old book written about the building and flying of the replicas for "Those Magnificent Men in their Flying Machines" covered this very subject in great detail. The Antoinette Monoplane replica made for the movie handled horribly at first, until they reluctantly retrofitted ailerons (and even then, didn’t fly very good!).

What needs to be watched with warping at or near a stall is the phenomenom of “control reversal” – the wing you expect to go up may in fact stall first, and fall! Add to that the adverse yaw of that same wing, and you can start to see the problem.

Art has commented that most of the “acrobatic” moves that his Eindekker does use the tailfeathers, not the warping. The warping does roll the airplane, albeit somewhat sluggishly. Art has posted here on the ‘drome recently (c.f. the Hoosier Dawn Patrol thread in Upcoming Events), so a note to him may get more information. You can also probably get him a note through the R/C Dawn Patrol website

http://www.bealmear.com/dawn_patrol/

So . . . .

Warping does work, even on our smaller models, it just has some nuances that are going to be different than aileron models. Keep the nose down when turning, and all should be okay. And use the rudder!

Best regards,

Lee McDuffee
the WinterHawke

Lucky Dog · 1 September 2006, 09:43 AM

Brequet,
I sent a link to this post to Art this morning. He'll post a reply soon I'm sure.

I was at his shop last night as matter of fact (looking at his 1/3 scale Nieuport 11 project). Although he's really had a great time with his E-1, and has learned a lot, he's really looking forward to having a plane with ailerons.

AeroClassics · 1 September 2006, 12:51 PM

Wow! Man, what terrific information! As I am considering starting my 1/4 E-III soon this is great information. I do not know how much Art's tips move (I will wait to see if he jumps in here) i know my plans call for 2" up and down. Seems like a lot to me, but that's what is called for. Sounds like a wing warper can be a bit of a handfull to fly. Might be better to fly it as a bit 3 channel system and use the wing warping as a scale feature!

Doug

Breguet · 1 September 2006, 05:29 PM

Thanks all! I hope Art will post. I had heard of the control reversal - is it only apparent at slow speeds (someone actually suggested you should set them up reversed but that goes against the grain)? I always intended to use heaps (about 80%) rudder mixing and have made sure the full flying rudder gives me lots of deflection. I shall probably post a link to utube or some of the mechanism work (and link it to here). Anyway I'll keep you all informed!

rcart · 1 September 2006, 05:34 PM

Hey fellas, Art here. Wing warping is a very interesting subject. My project, 1/3 scale Fok EI, was inspired by Bob Holman plans for a 1/4 scale Fok EIII. This was a Dana Lockwood design, I think, from the late seventies maybe early 80's.....I forget exactly when. Any way, since Lockwood's design was very similar to Anthony Fokker's design, it looked like it would work ok, eventhough I had never before done anything like it. I figured anyone building an eindecker would build the EIII, so I changed mine to an EI. There are a lot of suttle differences between those two aircraft.
The wing moves about 1 & 3/4 inches each way, up and down. Maybe a little less. When I was building and first hooked up the warping mechanism, I had a lot more movement in the wing panels. In fact I heard wood and glue joints breaking...... I put on smaller servo arms and have not experimented with increased movement since. I have wanted to, but if it ain't broke - don't fix it!
The plane flies very well, but the contols are not balanced at all! By that I mean that the same movement of the control stick for each axis gives a differing amount of roll, pitch or yaw. The rudder and elevator are very responsive and the wing warp is extremely sluggish in comparison. Wing warp is effective, but SLOW ! To turn, I imput both rudder and wing warp to start the turn and then finish the turn with rudder and fly the wing warp in the opposite direction to bring the wings back to level. Like Lee already mentioned, the hard manuvering is done with the tail feathers. It is difficult to get it all working in harmony and also keep your flying smooth. This is my third full season flying it and I think I have got the hang of it now. It is fun and a great flyer, but limited in its flight capabilites - much like the original must have been.
This project was my first attempt at a competition scale model. It has abtained static scores of 88.5 all the way up to 95 at various contests. I am very satisfied with the project.
Fire away ...... I will attempt to answer any questions you guys might have.
I have not experienced any control reversal or adverse yaw. Nor have I had trouble with slow speed or high angle of attack inputs leading to a stall. Every plane has its own unique slow flight/stall envelope to learn. Nothing really different here for me. Maybe sometimes when I try to roll it and when it is upside down, these things happen.....it is hard to say as it is not predictable in this attitude. It will barrel roll and sort of snap roll, but it will not wing warp roll.

AeroClassics · 2 September 2006, 08:32 PM

Thank you Art! I have the plans from Holamn and his laser cut parts for the Lockwood 1/4 scale. You have me itching to get started. It will be the mo9st unique aircraft in our club next to the Vickers Vimy that is being campaigned. One question I do have is did you use one or two sevos. Mr. Lockwood shows two. But I don't think servos were quite as strong 20+ years ago as they are today.

Thanks,
Doug