Thermal Hunter Mark II (oz3173)


Thermal Hunter Mark II (oz3173) by Frank Zaic from Popular Science 1939 - plan thumbnail

About this Plan

Thermal Hunter no 2. Rubbber sports model. Includes 2nd page with formers.

Quote: "Fast-Climbing Model Plane. Hunts out thermal air currents to increase duration of flights. By Frank Ziac, Editor of 'Model Aeronautics Year Book'

BECAUSE of the thorough testing it has received, you can be sure of the stability of this new 36 inch model airplane, Thermal Hunter No. 2. It is a powerful, high-climbing model that gets quickly into the air where thermals are more numerous. At the same time, it is of sturdy construction and won't readily crack up.

As an example of the importance of testing, it will pay the student of model aerodynamics to study carefully the slight differences be-tween the photos and the working drawings. The photos were taken during construction and just before test. flying, while the plans show the modifications which were made as the result of the tests. The rudder area had to be increased to make the model perfectly controllable. Although correct rudder area is very important, we have no way at the moment of calculating it accurately in advance.

Another addition was a central spar in the stabilizer. The center section of the wing was also covered with sheet balsa to protect it from the rubber binding. These seemingly minor points count a great deal.

Fuselage. Lay out full-size side views on paper and make the two sides. Daub the brace and longeron junctions on the working drawings with soap to prevent fuselage sides from sticking to the paper. Cut the semi-round bulkheads. Cement bulkheads and front stringer in place. Cover front portion with 1/32 in balsa and insert turtleback stringers. Make landing gear and rubber anchorage as shown. If you cannot obtain large face bushings, use tubes, but cement and bind them with silk to the longerons..."

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Thermal Hunter Mark II (oz3173) by Frank Zaic from Popular Science 1939 - model pic


Thermal Hunter Mark II (oz3173) by Frank Zaic from Popular Science 1939 - pic 003.jpg
Thermal Hunter Mark II (oz3173) by Frank Zaic from Popular Science 1939 - pic 004.jpg

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