Complex sentence: Then-Major Chuck Yeager was assigned to investigate the crash, and replicated the malfunction at a much higher altitude; this height advantage allowed him to safely regain control of the aircraft before it hit the desert floor.
Split into simpler sentences: Then-Major Chuck Yeager was assigned to investigate the crash and replicated the malfunction at a much higher altitude. This height advantage allowed him to safely regain control of the aircraft before it hit the desert floor.