The earlier 747-136s that BOAC bought had a max takeoff weight of 332.9 tonnes, a figure I still remember well. Incredible to think that the later Boeing 777s have a max takeoff weight of 7 tonnes more than that. When entering cloud at certain temperatures on the early 747s the flight engineer had 12 switches to turn on, 8 ignition and 4 nacelle anti-ice, the flight engineer also had to switch on fuel heaters.