The Federal Aviation Administration is investigating the crash of a crop duster in northeast Iowa. Fifty-nine-year-old Ronald Cook of Salix was piloting an airplane just south of Aplington at about five o’clock yesterday when he made a U-turn, struck a power line, and crashed into a bean field. Cook was taken to a Waterloo Hospital. His family has asked that his condition not be released. The aircraft was demolished in the crash. Power in the area was disrupted, but the Grundy County REC repaired the lines within an hour.