Boeing B-377 Startocrusier NorthwestBoeing 377 Northwest Airlines airplane model. The Boeing 377 was a commercial transport development of the Model 367 (military C 97). The first flight of the prototype was made on July 8, 1947, and was subsequently delivered to Pan American, to become the biggest user of the Stratocruiser. There were a variety of interior configurations accommodating from 55 to 112 passengers, or, if equipped as a "sleeper", with 28 upper and lower berth units plus