Radio Control Soaring by Dave Hughes Good condition. 268 pages. This is a brilliant manual form the early seventies on the subject. Covers more or less everything in huge and exhaustive detail with a profusion of photos,diagrams and line drawings.
A few headings from the many chapters:- Mechanics of slope soaring / Rudder only soaring / The pylon race soarer Creative soarer design / Introduction to thermal soaring / Aero towing / Aerofoil sections etc.
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