Happy Face (oz6453)

About this Plan

Happy Face. Radio control soarer model.

Quote: "A Standard Class sailplane that has logged hundreds of flights, many over an hour in duration. Equally at home on a slope or in a thermal, its structural integrity is designed to withstand virtually any maneuver or rough landing terrain. Happy Face, by Erroll L. Williams Major, USAF Retired.

Having flown as well as towed full size sailplanes, it was only natural that my first interest in RC model aircraft would center around gliders. After learning the basic skills involved in both thermal and slope soaring, albeit numerous mishaps including three near wipeouts, it was with keen interest that I welcomed the RCM series of articles on Basic Sailplane Design. Here were the needed parameters and relationship one to another that would enable me to develop my own ideas into a model that should truly perform. Then the issue of R/C Modeler arrived announcing the annual RCM Design Contest. This was the final impetus and I was off and running.

The experience I gained while constructing and flying two sailplanes from kits led to the establishment of certain criteria which are incorporated in Happy Face. These criteria include the following: provide space for a 500 mah flat configured battery pack to fit in the most forward nose compartment; reduce drag by eliminating rubber band wing attachment and attendant dowels protruding through the fuselage; minimize tail weight through light construction and minimal tail moment arm in order to keep ballast to a minimum; conventional construction and building techniques to stay within the skills of the average modeler; and finally the resulting model must be stable during a hi-start launch.

Let's get started with the construction.

Fuselage: The flat bottom fuselage allows construc-tion directly over the plan to assure perfect alignment. The 1/8 plywood bottom gives required strength and provides for a simple tow hook installation. Bulkheads and for-mers 1 through 5 are constructed of 3/32 plywood while 6 and 7 are made from 1/8 sheet balsa. Drill 3/16 diameter holes in bulkheads for Gold'N-Rod installation be-fore fuselage assembly. The hole location for these will depend on the servos used. The plans show the correct location for a Hobby Lobby 5 installation.

Construct the fuselage bottom using the plan template for a pattern. Notches for the bulkheads provide for positive-lock assembly. If not desired, the bulkheads must be shortened accordingly. The fuselage sides are made from 3/32 hard balsa and are cut to the size indicated by the heavy arrows on the fuselage side view. Glue the 1/4 x 3/32 spruce stringers to the fuselage sides prior to assembly as well as the 3/32 square soft balsa longerons aft of the wing. Be sure to taper these for a close fit at the aft end to assure a sturdy structure for the tail loads.

Glue the bulkheads to the fuselage bottom making certain that they are perpendicular. Next glue both sides in place making sure that they contact all bulkheads. The nose block is made from three pieces of one inch pine board cut to shape and laminated. Bore a 3/4 hole for ballast. The nose block is now glued in place and sanded to fit. Rough shape the two balsa blocks and glue to the top of the forward nose..."

Errol Williams' Happy Face from RCM issue 09-76.

Direct submission to Outerzone.

Supplementary file notes

Article pages, text and pics.

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