Weight limit discussion

[Earl Vincent]

You are on the right track Terry, the weight being increased and still keeping the plane 2x2 meter, to support the added weight the plane is going to get fatter in that 2 meter box, most of the current wing designs in the 960-1000 sq in range will handle 12 lbs at the desired slow flight speeds although after adding the width of the fuse on the wide bodys the squares are probably closer to 1050.
I have read most of this thread and have not seen anything about the fuse side area needed to support the added weight and where the side area is located in reference to the CG. Some of the older design fuses looked like pencils and doing controled knife edge at slow speeds was not possible with out a 45 degree angle of attack.I feel that is why more pilots are not flying these in competition much when slow flight speeds and keeping in the box are in demand for decent scores.  There is no height limit to the fin, canopy etc., to get the fuse loading down to fly slow and in close is going to take more side area which makes the plane a sail in heavy cross wind conditions. 
Every change is a trade off but most current designs are very balanced wing area to side area and a joy to fly if the weight is in the 10-11 lb range. It will be interesting to see where this whole thing is going and what we will be flying a few years from now. Is the reason for all this about power options i.e.,electric and gas? I do not understand why the limit is being changed to begin with.

Earl Vincent

From: Terry Brox 
  To: discussion at nsrca.org 
  Sent: Friday, February 25, 2005 7:13 PM
  Subject: Re: Weight limit discussion


  One must remember history to help here. Has any past changes ever brought the cost of pattern down? I believe it has always made it more expensive such as what happened with engine displacement.
         I am envisioning a new pattern plane for the new weight.
  It will be a monoplane, 78" ws, 78" length, fuse height 18", fuse width 10", wing root 25", wing tip15", 15degree sweep at the quarter chord, 12% airfoil making the wing root 3" thick, stab 28" and nearly 2" thick. 
         I hope it doesnt look exagerated, but I would be afraid this would be the trend. Obviously I dont know to what extent the poor flying quality of this kind of design would be, but who knows what could happen. 
         Classic case of opening one door into a room full of doors. 
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