Boeing's model 377 was developed from the WWII B-29 bomber. Named the Stratocruiser, this four-engine passengerliner bridged the gap for Boeing from wartime production to the introduction of the 707 jetliner in the late 1950s. The Stratocruiser, which set the standards for luxury air travel, represents a romantic airliners of the golden age of commercial aviation. Airliner Tech Volume 9.