747-300
The most visible difference between the -300 and previous models was a stretched upper deck with two new emergency exit doors and an optional flight-crew rest area immediately aft of the flight deck as standard. Compared to the -200, the upper deck is 23 feet 4 inches (7.11 m) longer.[135] The stretched upper deck had previously been offered as a retrofit and first appeared on two Japanese 747-100SR aircraft.[135] The -300 has a new straight stairway to the upper deck instead of a spiral staircase on earlier variants.[72] The staircase creates room below and above for more seats. With minor aerodynamic changes, Boeing increased the -300's cruise speed to Mach 0.85 from Mach 0.84 on the -200 and -100 models.[135] The -300 features the same takeoff weight. For available engines on the -300, the Pratt & Whitney and Rolls-Royce engine versions were unchanged from the -200, but the General Electric engine changed to the CF6-80C2B1 version