Robert Bob Tiedemann, a lifelong sailor whose passion for the beauty and versatility of vintage yachts passed away yesterday at Miriam Hospital in Providence, R.I., following a four month struggle with pancreatic cancer. He was 56 years old.His passion for classic yachts inspired him to rescue a substantial number of antique sail and power boats from old age and disrepair. Two of his sailboats, Gleam and Northern Light, both pre-World War II-built 12-Metres, were immortalized in one of the most famous yachting photographs of all time, Flying Spinnakers, by the late Morris Rosenfeld. Mr. Tiedemann combined his love of antique yachts with a thriving business by convincing corporate clients that racing his 12-Metres would make a good team-building exercise for their employees and clients. He started out in 1976 by chartering Gleam on Narragansett Bay, near his home in Newport, RI. It was an emotional decision, Tiedemann once said about his efforts to restore Gleam and Northern Light, both of which were largely in ruin when he discovered them abandoned in boat yards. After restoring their wooden hulls to pristine condition, he realized that people could identify with the class because 12-Metres were still sailing in the Americas Cup races 1958-1987 at that time. All of a sudden, these boats have a reason to live, said Tiedemann of yachts that many thought had outlived their youthful charm and purpose. The idea of restoring old 12-Meters inspired restoration work by others who saw Tiedemanns success. Because of his efforts, there are now as many as a dozen vintage 12-Metres being chartered and raced off Newport each summer. While his boats never actually competed in the Americas Cup, they were part of the same race class. Gleam, built in 1937, was once used as a Cup ?trial horse.? Mr. Tiedemann once estimated that he spent 13, 500 hours at the helm of the 68-foot Gleam. His restoration efforts have brought him restoration acclaim, including Preserve Rhode Islands Maritime Heritage Award in 1999. Bob grew up in Greenwich, Conn. His father was a naval architect and his family often sailed on Long Island Sound. Bob, who used to sneak into yacht yards as a child to admire boats, convinced his father to buy the 54-foot wooden yawl, Mariner, in the mid-1960s. Mariner, which was built in 1950 in Germany, set his destiny when he realized that he could make a living by chartering. Mr. Tiedemann and his wife Elizabeth, whom he married in 1994 aboard Gleam, operate their business, Seascope Yacht Charters, out of Newport. Through the years, the company grew as the couple discovered other important boats that captured their interests. Seascope currently has six vintage yachts in its fleet. In addition to the two 12-Metres and Mariner, they also have restored and charter Pam, a 62-foot luxury wooden powerboat built in 1921 as a Great Lakes commuter boat; and Fawan, a 40-foot glass cabin launch built in 1911 for John Jacob Astor IV. A sixth yacht, the 62-foot LAllegro, sits under plastic wrap in the couples back yard waiting to be restored. The express cruiser was slated to be the couples next labor of love. Mr. Tiedemann is survived by his wife, Elizabeth; his mother, Gertrude, of Bear River, Nova Scotia; his two sisters, Janet Whitney, of Newport and Susan Comeau, of Bear River; and three nieces. Mr. Tiedemann was a member of the New York Yacht Club, Antique Classic Boat Society and an honorary member of the Ida Lewis Yacht Club. Bob was also an avid gardener, snow skier, antique collector and nautical historian. A memorial service is planned for Mr. Tiedemann at Trinity Episcopal Church, Friday May 12th, at 3:00 p.m. The family asks that in lieu of flowers, donations be made to the Trinity Church Restoration Fund in honor of Mr. Tiedemann, or to the Robert H. Tiedemann Restoration Fund at the Museum of Yachting, an organization in Newport that Mr. Tiedemann helped form in 1980.