MANSFIELD - A single-engine plane carrying four men nosedived into rocky underbrush just off a runway at Mansfield Municipal Airport after it struggled to take off yesterday, killing two of the men and seriously injuring the others. The 1973 Cessna 172 appeared to accelerate slowly when it began its takeoff roll at about 10:45 a.m. and wobbled as it left the ground, said Aaron Galvin, of Oak Bluffs, who landed his plane on the same runway just after the Cessna took off. Read full story about Cessna plane crash.