Stall Proof Gassie (oz14391)


Stall Proof Gassie (oz14391) by Robert Hayos 1941 - plan thumbnail

About this Plan

Stall Proof Gassie. Free flight power model. Wingspan 40 in, wing area 240 sq in.

Quote: "Here's a trim looking craft that is good in performance, with an added feature that assures your efforts of being worthwhile. The Stall-Proof Gassie, by Robert Hayos.

IT WASN'T long after the end of the first World War when the England Handley Page Aeroplane Company developed a device that startled the aviation world. They had equipped one of their huge planes with an airfoil-shaped vane which ran along the leading edge of the wing and a few inches in front of it. This was the first 'wing slot' ever used on a flying machine.

The men who designed it realized that a device to prevent stalling was absolutely necessary, and the slot was the answer to those demands. As a plane neared the stalling speed, the angle of attack was of course increased. The wind hitting the wing at a steep angle was deflected off and the airfoil soon lost its lift.

Although the slot did not prevent this entirely, it did allow the craft to assume a higher angle of attack. The wind striking the slot and being deflected down onto the wing proper forced the plane to keep its flying speed. Because of this, a higher rate of climb could be achieved which resulted in increased performance.

When the author first realized the possibilities of wing slots being used on a model, it became evident that here, too, stalling would be impossible and the climb would be increased appreciably. Also, spiral stability would be enhanced.

Up to this point not much has been said about the ship itself. This little job was designed when the old rules were in existence, which limited the wing area to 225 square inches for Class "A" models. Since then the rules have been changed and the ship has competed against much larger models with favorable results. And although the ship has never actually been entered in competition, it has outfiown many craft with much more power and wing area and has earned its salt in all types of weather. The plane has a near vertical climb and exceedingly flat glide. Under power it is extremely fast and inherent stability keeps it going smoothly without spinning tendencies.

The combination of slots and simple design have been the secret of success of this model. The slot design explained here can be used on your own plane, provided the slots are scaled proportionally to the plane itself.

Fuselage: The fuselage is made first in the following manner. Begin by laying out the drawings on a large sheet of paper. Shelf or brown wrapping paper serves the purpose nicely. The fuselage sides are pinned to place on the plans, one side being made at a time. The longerons are of medium hard stock, while the cross braces are made of softer material having the same dimensions. Sheet balsa, 1/8 thickness is laid between the first upright and diagonal, its grain running vertically.

The wingmount is made of balsa plywood having 1/8 sheet balsa runing vertically in the center and 1/16 sheet on either side running horizontally. Sand the entire mount to a streamline shape, The mount is then glued firmly to a piece of 1/16 sheet which previously has been glued across the top longerons..."

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