In an unusual move on Tuesday, the NTSB issued an "urgent safety recommendation" asking the FAA to prohibit further flight of the Zodiac CH-601XL, which has been involved in six in-flight structural breakups since 2006. The board cited four accidents in the U.S. and two in Europe in which a CH-601XL broke up in flight, killing a total of 10 people. According to the NTSB, there is a problem with the airplane design that makes it susceptible to aerodynamic flutter -- a phenomenon in which the control surfaces of the airplane can suddenly vibrate, and if unmitigated, can lead to catastrophic structural failure. The NTSB wants the U.S. fleet grounded until the FAA can determine that the problem has been solved. "The NTSB does not often recommend that all airplanes of a particular type be prohibited from further flight," said NTSB Acting Chairman Mark Rosenker. "In this case, we believe such action will save lives. Unless the safety issues with this particular Zodiac model are addressed, we are likely to see more accidents in which pilots and passengers are killed in airplanes that they believed were safe to fly."
This is a companion discussion topic for the original entry at https://www.avweb.com/news/ntsb-asks-faa-to-immediately-ground-zodiac-ch-601xl-aircraft