Chase J. Nielsen, a navigator on the 1942 Doolittle Raid on Japan who spent 40 months as a prisoner of war after participating in the air assault that lifted American morale only four months after the Japanese attack on Pearl Harbor, has died. He was 90.

Nielsen, a retired Air Force lieutenant colonel, died March 23 at his home in Brigham City, Utah, said his wife, Phyllis.

On the morning of April 18, 1942, 80 volunteer airmen on 16 B-25 Mitchell bombers took off from the deck of the aircraft carrier Hornet more than 600 miles from Japan. They were about 200 miles farther out and took off earlier than they had planned. They were forced to move up the operation after the U.S. task force was spotted by Japanese picket boats.

Nielsen, then a 25-year-old lieutenant, was the navigator for Crew No. 6.

Led by Lt. Col. James H. "Jimmy" Doolittle, the 16 planes bombed targets in Tokyo and several other cities.

Because the bombers could not land on a carrier, plans originally called for them to land at airfields in China during the day. But with fuel running low, primarily because of the increased distance and bad weather, the airmen were forced to ditch their planes or bail out over or along the Chinese coast at night; one plane diverted to Russia.

Nielsen was in one of the two planes that ditched off the coast, and two men were killed. He was later found on shore by a Chinese guerrilla and he joined up with his pilot and co-pilot. Japanese forces occupying China eventually found them and they and five others became prisoners of war. "Being a prisoner was something I had never prepared for," Nielsen told the Salt Lake Tribune in 1995. "It takes all the wind out of your sail, if you had anything left."

Nielsen and his fellow prisoners, who were taken to Tokyo, were beaten and tortured while being interrogated. Three of the eight American airmen were executed after a brief trial; Nielsen and the four others were sentenced to life in prison in solitary confinement and shipped to a small brick cell in Nanking, where one of them, weakened by dysentery, later died.

Nielsen and the other three imprisoned Raiders were not freed until the end of World War II. "Four Came Home," a book by Carroll V. Glines, chronicles their story.

Nielsen returned to China in 1946 to testify against his former captors in the war crimes trials in Shanghai.

After retiring from the Air Force in 1961, he worked as an industrial engineer at Hill Air Force Base in Utah.

"I am proud to have been on the Doolittle Raid," Nielsen said at the Raiders' reunion last year. "I am more proud to have been of service to my country. I hope and I pray that what we Doolittle Raiders have done will be an inspiration to you people."