March 4 2016: Over the last two weeks I have been questioning the design of the top wing centre section. My question first came from my incorrect reading of the plans for the front cabane attach points of the fuselage. What I thought the plans were saying was to have a single front sway wire. This was in part influenced by a photo I had seen in a thread in the Biplane Forum.
Turns out that the sway wire fittings are a dual pair of wires, not a single.
What I did uncover in the course of this is that the sway wire design changed in 2006. This occurred when some hand drawn Curtis Pitts plans were changed to CAD. The biggest change was the sway wires moved from the centre section rear spar to the front spar. A whole heap of debate ensued and it will result in me modifying the plans and moving the sway wires to the rear as per the Pitts model 12.
If you want to see the whole story have a look at this thread. This is really worth a read if you are considering building the three piece delta wing. Make up your own mind!! Biplane forum R&D Design