VP for F1D
For the longest time, Bob DeBatty was intrigued by the idea of building a variable-pitch (VP) propeller for his F1D models. He knew that others had tried VP with some degree of success, but to the best of his knowledge all of the previous designs had some problems. Many worked from the tension of the rubber motor, requiring an adjustment whenever a different-size motor was used. Others were designs for two-position props; when launched they were at high pitch, then as the tension decreased to a certain amount, they would switch to low pitch, with nothing in between.
