Howard Hesseman, a prolific character actor who became a beloved TV mainstay through his roles on sitcoms WKRP in Cincinnati and Head of the Class, died over the weekend in Los Angeles of complications from colon surgery he had undergone last summer, Variety reported. He was 81.“Howard was a groundbreaking talent and lifelong friend whose kindness and generosity were equaled by his influence and admiration to generations of actors and improvisational comedy throughout the world,” said his manager, Robbie Kass, according to Variety.With his signature long hair and handlebar mustache, Hesseman found his most iconic role-playing radio DJ Dr. Johnny Fever on the CBS sitcom WKRP in Cincinnati. Hesseman earned two Emmy nominations for his work on WKRP, which hailed from MTM Productions and ran on CBS from 1978 to 1982. Hesseman was also well-known for his 1986-1991 starring role as Charlie Moore on ABC’s ensemble comedy Head of the Class, playing a teacher at a Manhattan high school for high achievers. He also joined the cast of the long-running CBS comedy One Day at a Time for its ninth and final season in 1982-83.Beyond television, Hesseman also appeared across several films over his five-decade-spanning career, with credits including Police Academy 2: Their First Assignment, About Schmidt and This Is Spinal Tap.