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Hi Fellow wood worms,
I am half way though the build of a unusual canard bipe which was designed by the late Dough Mc Hard as a free flight twin and as he did not get to finish the plan i have know idea where the balance point is . Has anyone built one and know where the balance point is ? . I could build one out of polystyrene as a glider and add weight until it gilds correctly . Can any one help on this ?
Cheers
That sure is one ‘crazy’ model.
I guess you are building it for freeflight??????
I can only guess that the C of G would be about 1/3 to 1/2 way along the fuselage.
I think it might be a ‘suck it and see’ situation.
I guess best when it’s done take it with some clay to add to either end to the long grass and see how it glides before the power goes on.
Good luck and keep us informed please.Doug McHard did do lots of good models in his day, so I guess he would have expected it to fly.
Stephen,
Don’t know if this helps but on the March 1963 AeroM there is a Canard by James McCann in the article he quotes “rigging angles can determine the CG position” which is then finalised during trimming. The reason I know is I am building a TD010 size one as the moment for fun!!!! Let me know if you have better info.Way back, I watched the late Jim McCann flying a number of canards, from .010 up to .15 … very impressive when sorted.
Hi guys,
Thanks for the reply s, I think on question of where the cog is going to be a matter of choke it and see where to add weight , although grass is short and wet at the moment .
On building this model i have come across many errors and so i have had to re draw the plan .Although i`am no drafts man i have re drawn the wings and nearly finished the building of them . I still have to re draw the fuselage and as i am having to draw the plans for myself i am designing the model for both free flight and as electric rc .
The original model was designed by Sgt D McHard whilst in the RAF for the RAF Nats at St Athens in May 1953 . It won its class category it was revised in 2000 unfortunately he died before the plans had been finalized .ModelAir the organizers of the model flying events at Old Warden setup a special awaed to be given for the best fished Cucumber2 present at Old Warden on their Doug McHard Day Sunday 27 July 2003 and with less than four months to get it built many may not of taken up the challenge.One foot note, this design does not look to different from the lay out of that of the wright brothers , canard bipe !
Hi again ,
here are some more pic of the progress not too sure how to power it yet as i do not have a DC dart let alone two of them . I have thought about a electric motor with a longer drive shaft that sticks out the front and back of the motor so that i can use the one motor as a push me pull ? . Still some time of yet as i will also have to make a chuck glider of the cucumber , polystyrene or some thing so i can find out where the cog is .
hi all its been some time now but i have now finished the test model .
As soon as i get some time to chuck it of some hill ill let you know how it whet i have managed to chuck it in my garden and it seems to fly ok 😮
here are some more pictures .
Hope this helps. There is a book entitled “ How to make Scale Models Fly” by Bill McCombs. There is more information in this book about model airplanes, both scale and free flight, than I have ever seen in one place. I refer to it often. I’m pretty sure there is a section that describes how to calculate the CG of canards.
The book can be purchased from Susan Creamer, 1925 Clark Trail, Grand Prairie TX 75052 $18.95
Hi stardust ,
sorry its taken me so long to reply but i have not many posts so i only check now and again , Thanks for the post ill see if i can get that book here in england manchester . In the mean time i`ll have to wait until we get some good weather here in manchester. Would you believe it i get the chuck glider ready then i am put on call for a week and boy have i been busy , nice weather we had too then the week i am off call it peas it down all weekend . I guess i`ll have to wait another week now . My free flight experience is limited to gliders and rubber power and i tried co2 but the less said about that the better , so with an unusual model like this you can see why i am a bit cautious . 🙁Well I had me first powered test flight today and although I know the model was under powered I decided to give it a go. It had been threatening to rain all day and I had been putting it of long enough so off to the park I went with my son. There was a light breeze and with a firm throw i launched the model it did not gain much hight but did fly a full circuit landing not too far from where I had launched it . I tried several more flights all were pretty much the same , proving my balance point and wing angles to be fine .Although I need a more powerful motor and a prop shaft to carry the second prop which will provide the extra push this is where the next problem begins as I will not be able to use a propeller larger than 5.5in in diameter as it would hit the fuselage . The balance point is 120mm in front of the leading edge of the lower rear wing .Now I just need to get a more powerful motor and a prop shaft to complete the final model then after final testing add the C of G to my plan .
😀
Just thought i`d share some pictures,
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