Francis Yohannan, 79, a retired Air Force lieutenant colonel and World War II aviator who was an inspiration for the protagonist of Joseph Heller's darkly comic novel "Catch-22," died at his home March 17 after a stroke.

Col. Yohannan became friends with Heller when both were Army Air Forces bombardiers stationed on Corsica during World War II.

The title of Heller's 1961 novel referred to the near-impossibility of being excused from dangerous bombing runs. A flier could be grounded by being declared insane, but being afraid of such danger was considered virtual proof of sanity.

Heller, who died in 1999 at the age of 76, told USA Today in a 1998 interview that it was from Col. Yohannan that he "derived the unconventional name for the heretical Yossarian."

Heller said that the actual character of Yossarian was based on Col. Yohannan and other military personnel, including Heller himself.

Many others who served with Heller were upset about the novel, but to Col. Yohannan "it was all tongue-in-cheek," said his son, Lance Yohannan of Paradise, Mont.

Col. Yohannan turned aside questions from reporters who asked whether he was the real-life Yossarian. "He was a very humble man," his son said. "He would never bring up 'Catch-22' by himself or talk much about the war."

Col. Yohannan, a Philadelphia native, retired from the Air Force in 1974 after more than 9,000 hours of flying time during his career.

He flew 66 combat missions from Corsica aboard B-25s, and flew in B-36 bombers during the 1950s and B-52s during the 1950s and 1960s. As an air tactical officer, he flew aboard Phantom jets in Vietnam during the conflict there.

His military decorations included the Distinguished Flying Cross and the Bronze Star.