History.com - After 71 years, a British historian has located the final resting place for a heroic young Royal Air Force pilot who was listed as missing in action and presumed dead in May 1940 during World War II.

According to British newspaper the Telegraph, 22-year-old Flying Officer Derek Allen took to the skies for his first time in combat on May 10, 1940, the day that Germany launched its invasion of France and the Low Countries. Over the next eight days, Allen shot down four enemy aircraft himself and shared credit for three other downed planes. He would be awarded the Distinguished Flying Cross for his performance. Forced to bale out on May 15 after his Hurricane plane was hit with anti-aircraft fire, Allen walked for 24 hours through enemy territory in order to get back to his squadron.

About 6:30 a.m. on May 18, Allen was back in the air when a German gunner shot his plane down over farmland in northern France. By that time, German tanks and infantry had already managed to break the French defensive lines; they would soon advance to the coast. On May 26, the RAF provided much-needed protection from the sky as Allied forces were evacuated en masse from the French seaport of Dunkirk to England. Paris fell to the Germans on June 14, and defeated, France signed an armistice on July 22.

When Allen’s parents were first told their son was missing in action, it was hoped that he might have been captured by the Germans and still be alive. Much later in the war, a RAF adjutant visited to tell them his plane had crashed and he was presumed dead. When the war ended in 1945, Derek Allen was one of 40,000 missing British airmen.

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NOTE: It has been noted that the word "bale" is used above instead of "bail." The spelling provided is simply an alternative as chosen by the History.com editor.