Description

This is the Baby Bipe by Don Prentis, published in Model Airplane News.  The plan shows the top wing mounted on a pylon and secured by two screws that go down from the top of the wing, between the two center ribs.  There are outboard struts to prevent the top wing from rocking.

In my kit I’ve changed from the old fashioned full depth spars shown on the plan to modern top-and-bottom spars of 3/16″ square bass or spruce.  Two center ribs made of 1/8″ birch ply are provided for extra strength in the wing mounting structure.  You can place these ribs as shown on the plan, to provide a space in between for the mounting screws, or you can use the same top wing mounting method that I used in my modified version of the RCM Basic Bipe.  In this case you would laminate the two plywood ribs together and place them on the centerline.

Outboard struts are not provided because of irregularities that occur in building.  My preference is to make them from 2-56 push rods with clevises, and encase them in balsa sticks if desired.