the 744 has a higher mtow than the 340. it follows too that it has a higher mlw. at the same thrust setting, the heavier aircraft will have to fly at a higher aoa to generate the same lift. furthermore, the MAXcl should be increased to enable the aircraft to fly at slower approach speeds, and MAXcl is a function of aoa. the higher the aoa, the greater the need to energize the boundary layer, to create turbulent flow and thus delay separation within the boundary layer.