Posts: 99
Joined: 12/9/2002 From: Muncie,
IN, USA Status: offline
This is a built up wing. It takes me about 10 - 15 hours to build a wing and that includes cutting the ribs. Since there is no fuse and tail section, it is amazing how fast these wings go together. Covering the wing is a breeze.
I started on the 150" wing today. I built a mock-up of the wing center section structure out of balsa and foam core. It is almost 60" across. I need to build motor mounts, engine cooling ducts, custom made mufflers, engine heads and landing gear mounts and the mock-up with allow me to test fit the items before installing them in the actual wing. The engines (OS .46 FX engines with custom cranks allowing one engine to run clockwise and the other to run counter-clockwise) be mounted inside of the wing. It will take every bit of 90 days to build this wing.
Thanks to all who have requested that I contact them when the plans are finalized. I am keeping a list of email addresses. I appreciate your encouragement and interest in pure flying wings.
Posts: 21
Joined: 11/20/2003 From: lakeland, FL, USA Status: offline
Jeff,
Ya know, pictures are the greatest thing to hit the internet, and yours are very, very good. Your aircraft are just too cool for words. What method do you use to loft your ribs? I am currently trying the "new-fangled" method of using a CAD program and getting mixed results. Either the program I am evaluating doesn't talk swept delta or I am behind the learning curve.
Posts: 130
Joined: 6/24/2003 From: Argentina south, Chubut Status: offline
Hi Include me in the list for the airfoil etc. Bill Evans Slow Motion from Model Aviation plans make me a believer of Flying Wings concept. I am living in Argentina. The Slow Motion (a Simitar with changed name) have a Tower 40 . Have only flown 1/2 A and the MVVS 12 in three planes previously Have burnt 2 gallons of fuel. I am planning build a Desperado Three Thousand with a Homelite chainsaw 38cc engine converted Happy landings Jose
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The experience is a comb the life gives you when you are bald. "Ringo" Bonavena.
Posts: 99
Joined: 12/9/2002 From: Muncie,
IN, USA Status: offline
I am using an Eppler 334 airfoil from root to tip with 4 degrees of twist. I used a program called "TracFoil" to plot my ribs. I use QCad as my CAD program.
Posts: 3907
Joined: 1/19/2003 From: Spring Hill,
FL, USA Status: offline
4 degrees of twist = 4 degrees of washout? Is this a reflexed airfoil? Are the elevons neutral (with the airfoil) for flight or do they need to be up slightly?
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Work is what I do for the love of it. A job is how I pay for it. :) Please visit AirfieldModels.com
Posts: 99
Joined: 12/9/2002 From: Muncie,
IN, USA Status: offline
The Eppler 334 airfoil is a reflex airfoil. See the attached graphic.
Yes, 4 degrees of twist is 4 degrees of washout. This is a continous twist from root to tip. You achieve this by building the wing panel on a special jig made out of foam core. Depending on the length of panel, the root end of the jig is about 4" tall and the tip end of the jig is about 3/4" tall. See the picture below of the wing panel on the jig.
Wings are flown out of trim in pitch. At low airspeeds you will have the wing trimmed with elevons slightly up....in my case, about 1/4 inch. However, at high airspeeds with the plane trimmed with the elevons up 1/4", I must apply significant down elevon to prevent the wing from climbing. What I do is launch my wing with the elevons up 1/4", then trim the plane for level flight at 1/2 throttle. At 1/2 throttle, the elevons are flush with the wing. A wing will pitch up when airspeed increase and pitch down when airspeed decreases. When I increase thottle, I will have to input down elevon to maintain altitude....otherwise it will climb.
Jeff
< Message edited by NorthropN9M -- 12/21/2003 11:28:28 PM >
Posts: 3907
Joined: 1/19/2003 From: Spring Hill,
FL, USA Status: offline
Great! Thanks. That's all I need to know. The first photo will give me enough info about sweep and taper and I can take it from there. I appreciate your willingness to share your work and the results of your research.
Best regards,
Paul
_____________________________
Work is what I do for the love of it. A job is how I pay for it. :) Please visit AirfieldModels.com
Posts: 130
Joined: 6/24/2003 From: Argentina south, Chubut Status: offline
Hi Many thanks for put your long hours working with flying wings in this site to make our hobby more rewarding. I will start to build with your instructions help . My desire you have great success with your flying wings . Merry Christmas Happy 2004 year with many more flying wings. Happy landings Jose
_____________________________
The experience is a comb the life gives you when you are bald. "Ringo" Bonavena.
Posts: 1458
Joined: 2/2/2002 From: Lakeside, AZ, USA Status: offline
Jeff Thanks for your time with us. A flying has always interested me. I am confused on your trim,I helped a friend fly a simatar < no tail > a couple years ago and I am almost possitive we had to trim the elevaons down to get it to lift off. With the elevaons down they should give lift, The same with an aileron in the down possitation will raise that wing tip. Am I missing something? I have been thinking about your big wing with multi engines that is going to be a challange will you hook your split ailrons to the rudder controll on your TX? I would like to build my first wing out of foam with about 85 in WS. I have a friend that will cut me one . I don't expect the first one to last very long. I would assume on a flying wing you don't need as big of motor as you would need on a conventional plane. Thanks again and have a good Hollidays
Posts: 99
Joined: 12/9/2002 From: Muncie,
IN, USA Status: offline
Rich,
My terminology may be confusing. When I say "up elevon" this means that I am pulling back on the gimbal and the elevon is moving above the top surface of the wing. Just the opposite for "down elevon."
I fly with both hands -- both rudder and aileron and I do slave aileron off of the rudder gimbal. It's just a preference of mine.
Elevon is the mixture of both aileron and elevator in one control surface. So, my flying wings do not have a control surface dedicated exclusivly to roll control and a surface dedicated exclusively to pitch control. The elevon controls both pitch and roll.
Sorry about my confusing terminology. Thank you for asking me to clarify. Let me know if I did not understand your question.
You are correct about flying wings not requiring as large as engines as conventional aircraft of similar wing areas. The wing has less drag and there is less weight since there is no tail group of fuse. Plus, I fly the wing "on the wing" if you know what I mean. Top speed on my electric wing is only about 35 - 40 MPH on a dead calm day.
Always thrilled to answer questions. Please let me know how I can be of help.
Jeff
< Message edited by NorthropN9M -- 12/24/2003 11:36:24 AM >