Executive in Action: Philip Rolla, Propulsion System Inventor

By Wendy Laursen

Philip Rolla didn’t want to be a farmer like his father and grandfather. He was born in Madrone, a small agricultural town outside San Francisco, and farming was the family’s Italian tradition, but Rolla’s father believed in education and so his son was able to pursue a degree in engineering and economics and follow his own passions as they led him a long way from home.

His first passion was for racing boats and moving to Italy, Rolla radically changed the sport with his innovative propellers. “I was breaking all the rules as to what propellers should be like. When I started out it was, and had to be, two bladed propellers. I introduced three bladed propellers in 1964 and led with the innovation of more blades until I had them racing with six bladed propellers in the end,” says Rolla.

For 25 years, starting in 1963, he furnished all the important race winning propellers in all the important international categories from 250cc hydroplanes to F1 circuit and Offshore Class 1, all over the world. He also built the propeller that Tom Gentry used for his transatlantic record in 1989.

Rolla pioneered the development of surface piercing propellers firstly for racing and then for the other applications they are renowned for today – high speed patrol and pursuit craft. The initial development was at the request of Commander Peter DuCane of Vospers working with the Office of Naval Research. They were then taken up by Magnum Marine and used with Arneson surface drives from 1980. “These worked extremely well and so all Arneson surface drives had to have my propellers. In 1983 I had my first factory. Before that everything was done out of my garage – a real cottage industry with me making all the racing propellers with my own hands.”

Another passion has been instrumental to Rolla’s success and that is his love of minimalist art. If he hadn’t been familiar with conceptualism and minimalism, mostly in the works of Donald Judd, Water de Maria and Dan Flavin, he would never have had some of the crucial intuitions that proved to be decisive in his industrial research.

The factory grew to employ 50 people and during this time Rolla was the first to apply computational fluid dynamics design to traditional fully submerged propellers for commercial use. Recognition for his innovations has included being invited to be part of a MIT consortium for high speed propulsors and the 2000 RINA small craft medal for the design and engineering of surface piercing propellers.

In 2004 Rolla sold the business to Twin Disc. “Accounts receivable, balance sheets etc are not really for me. I never tried to make Rolla into a big company, only big enough to allow it to make the best one-off propellers possible.

Without day-to-day responsibilities for the business, Rolla is devoting more time to research. “I feel I have paid my dues to business and am free to use my experience and imagination as I wish.” The results have been more patents including one for an improved blade geometry for surface piercing propellers that improves the distribution of pressure and control to wetted and ventilated regions of the blade to give greater propulsive efficiency. He has also recently patented a waterjet design that enables at least two waterjets to be powered from a single power source. This allows for the uncoupling of power to either one of the waterjets. Because the waterjet diameter required for low-medium speed conditions is approximately double the area that is needed for efficient high speed operation, a twin system can be used provide greater efficiency over a range of speeds.

Engineering and art continue to be combined with Rolla’s establishment of a private museum and art gallery in an old kindergarten outside Bruzella, Switzerland, where he now lives. The latest photographic exhibition is based on the history and spirit of houses. It combines his passions for art, engineering and simplicity and includes an image from the area he grew up in back in California.

Wendy Laursen can be reached at [email protected] for questions or comments.