The Pan Am 747 in background. The mid-1960s saw the development and introduction of many new jetliners. None, however, has matched the dramatic impact of the 747. Increasingly crowded skies and the availability of large-thrust engines added to the incentive for creating the giant 747. It all began with the 747-100, the first in the 747 Classics series, which also includes the -200 and -300 models.