Complex sentence: The Maytag family sold their stock in March 1962 to the Goldfield Corp. Lewis W. Dymond became president of Frontier and under his guidance, Frontier started to provide service with Boeing 727s on September 30,1966, calling them Arrow-Jets.
Split into simpler sentences: The Maytag family sold their stock in March, 1962 to Goldfield Corp, at which point Lewis W. Dymond became president of Frontier. Under Dymond, Frontier started service with Boeing 727s on September 30,1966, calling them Arrow-Jets.