The 4-40 Bipe by D B Mathews was published in RCM and kitted by Ace RC. The incidence of the top wing is set with a jig, which is shown on the plan and was included in the Ace kit. My short kit includes this jig.
Please note that as is the case with most Mathews plans, there are some discrepancies between the shape of the rib and the shape of the wing saddle, but all of my parts should match each other.
Wingspan is quoted as 48″. I measured it on the plan at 49″. I think the mounting blocks for the top wing look pretty questionable, so I’m including a few plywood ribs to strengthen the joints.
Ken Cigler has kindly shared photos of the 4-40 Bipe he built. It’s a really nice looking plane.