Some Sailing Science
David Roseman
January 15, 2025

Before it became a clothing store, Land’s End was a sailboat hardware vendor in Chicag. It had a good store and very nice catalog. Jack Patterson, founder of Patterson Marine, was the first store manager. I don’t think that I met Jack then, but he remembered Joan and the kids. I frequently sent them to the store with a shopping list, often on a prescription pad. Jack and I caught up later in Pentwater.

The 1973 catalog pushed Aero-Hydrodynamics of Sailing by CJ Marchaj. I had just ordered my C&C 30, was interested in learning how to sail, and bought the book. Jack said they only sold 2 other copies, and he was sure I was the only one to read it. (Jack occasionally exaggerated.)

I had extensive experience with medical electronics and early computing (analog then digital). I daydreamed about using electronics to computerize Marchaj’s concepts. In the early 2000’s we at the PYC had seminars about sailing. I couldn’t find a good demonstration of the basic physics, so I wrote a program that I called WindInfo