Complex sentence: In 1911 she earned the first U.S. pilot's certificate issued to a woman by the Aero Club of America, and less than a year later became the first woman to fly across the English Channel.
Split into simpler sentences: In 1911 she earned the first U.S. pilot's certificate issued to a woman by the Aero Club of America. Less than a year later, she became the first woman to fly across the English Channel.