A US Navy pilot was shot down after making bombing runs over the tiny island of Chichijima during WWII.

He and nine fellow naval aviators had to evade their Japanese enemy. Only one managed to successfully avoid capture — and even then, it was all by luck.

It was 20-year-old Lt. George H.W. Bush.

For his book "Flyboys," James Bradley tracked down and researched official files and records from war crimes tribunals after the war. The fate of the other eight pilots, as he discovered, was absolutely horrifying.

George H.W. Bush during his time as a Navy pilot, seated in a Grumman TBM Avenger aircraft in 1944. US Navy

Bush and his wingmen encountered intense anti-aircraft fire over their targets. Bush's airplane was hit by flak before catching fire. He dropped his bomb load over the target, but was forced to abandon his Avenger Torpedo Bomber.

Like many prisoners of the Japanese, the captured men were tortured and killed using sharpened bamboo or bayonets. Many were beheaded.

Unlike many prisoners of the Japanese, however, four of the Navy pilots were slaughtered by their captors, who then had surgeons cut out their livers and thigh muscles — and then prepare the meat for Japanese officers.

Surgeons removed a four-inch by 12-inch piece of thigh, weighing six pounds. According to those Japanese survivors who were on the island, it was prepared with soy sauce and vegetables, then washed down with hot sake.

The future President Bush was further from the island when he bailed out of his aircraft. Floating in the water for four hours, he was protected from Japanese boats by American planes before being rescued by the USS Finback, a submarine that surfaced right in front of him.

George H.W. Bush being rescued by the submarine USS Finback, after being shot down while on a bombing run of the island of Chi Chi Jima, September 2, 1944. US National Archives

Bush didn’t know any of this until around 2003.

“There was a lot of head-shaking, a lot of silence,” author James Bradley told The Telegraph. “There was no disgust, shock, or horror. He’s a veteran of a different generation.”

While aboard the Finback, he assisted in the rescue of other downed pilots. He was aboard for a month before returning to his berthing on the USS San Jacinto. He earned the Distinguished Flying Cross, three Air Medals, and the Presidential Unit Citation during his WWII service.

Bush, who was the 41st president of the United States, died Friday at 94.