Read this: Soviet Premier Nikita Khrushchev announced that a "spy-plane" had been shot down but intentionally made no reference to the pilot. As a result, the Eisenhower Administration, thinking the pilot had died in the crash, authorized the release of a cover story claiming that the plane was a "weather research aircraft" which had unintentionally strayed into Soviet airspace after the pilot had radioed "difficulties with his oxygen equipment" while flying over Turkey. The Soviets put Captain Powers on trial and displayed parts of the U-2, which had been recovered almost fully intact.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): According to the cover story, what did the "weather research" pilot have trouble with?
oxygen equipment