Local sailing umpire David Blackman has a unique front-row seat at this week’s America’s Cup World Series races in San Diego. The 45-foot high-performance catamarans are so fast that the only way on-the-water umpires can keep up is with equally high-performance jet skis. Says longtime umpire Grant Baldwin, “Sailing umpires really need to get in as close as possible to the aciton on the water.” Blackman is one of two former Navy SEALs who were recruited for this event because of their background. For complete coverage of the AC World Series, see this Friday’s Newport Beach Independent.