A tiltrotor aircraft (10) is operable in a helicopter flight mode and an airplane flight mode. The tiltrotor aircraft (10) has an airframe including a fuselage (12) and a wing (18). First and second pylon assemblies (24a, 24b) are respectively coupled to the airframe proximate outboard ends of the wing (18). Each pylon assembly (24a, 24b) includes a mast (60) and a proprotor assembly (26a, 26b) operable to rotate with the mast (60) to generate thrust. The pylon assemblies (24a, 24b) are rotatable relative to the wing (18) to selectively operate the tiltrotor aircraft (10) between the helicopter flight mode and the airplane flight mode. The thrust of each proprotor assembly (26a, 26b) has a thrust vector with an inboard angle between about 5 degrees and about 12 degrees relative to an axis parallel to the yaw axis during hover operations, thereby reducing download on the airframe and improving hover efficiency.
展开▼
