Lynn Doyle Cooper
L.D. Cooper, a leather worker and Korean War veteran, was proposed as a suspect in July 2011 by his niece, Marla Cooper. As an 8-year-old, she recalled Cooper and another uncle planning something "very mischievous", involving the use of "expensive walkie-talkies", at her grandmother's house in Sisters, Oregon, 150 miles (240 km) south of Portland. The next day flight 305 was hijacked; and though the uncles ostensibly were turkey hunting, L.D. Cooper came home wearing a bloody shirt—the result, he said, of an auto accident. Later, she said, her parents came to believe that L.D. Cooper was the hijacker. She also recalled that her uncle, who died in 1999, was obsessed with the Canadian comic book hero Dan Cooper (see Theories and conjectures), and "had one of his comic books thumbtacked to his wall"—although he was not a skydiver or paratrooper.
In August, New York magazine published an alternative witness sketch, reportedly based on a description by Flight 305 eyewitness Robert Gregory, depicting horn-rimmed sunglasses, a "russet"-colored suit jacket with wide lapels, and marcelled hair. The article notes that L.D. Cooper had wavy hair that looked marcelled (as did Duane Weber).
On August 3 the FBI announced that no fingerprints had been found on a guitar strap made by L.D. Cooper. One week later they added that his DNA did not match the partial DNA profile obtained from the hijacker's tie, but acknowledged, once again, that there is no certainty that the hijacker was the source of the organic material obtained from the tie. The Bureau has made no further public comment.