Upon seeing the released report, Leonov also realized that his own account of that day had been recorded incorrectly. The report suggested that he heard the loud booms 15 to 20 seconds apart, when it was actually two seconds.
"That suggested that the two jets must have been no less than 50 kilometers apart." Leonov said.
Armed with the report's data, a new computer simulation was generated, revealing why Gagarin's jet went down.
"Now, a jet can sink into a deep spiral if a larger, heavier aircraft passes by too close and flips [the jet] over with its backwash. And that is exactly what happened to Gagarin. That trajectory was the only one that corresponded with all our input parameters," Leonov told RT.
Leonov was allowed to go public with the story, except for one detail: the Su-15 pilot's name. That pilot, who is now 80, is said to be in poor health.
"I was asked not to disclose the pilot's name," Leonov explained. "He is a good test pilot... It will fix nothing."
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