Abstract: Aircraft comprising an airframe having a forward end, an aft end opposite the forward end, a top extending between the forward end and the aft end, and a bottom opposite the top side. The aircraft further includes a power plant mounted on the airframe. In addition, the aircraft includes at least two propellers rotatably mounted on the airframe and powered by the power plant for moving the aircraft in a generally forward direction during operation of the propellers. Also, the aircraft includes at least two counter-rotatable fan sets mounted on the airframe and powered by the power plant for providing upward lift to the aircraft during operation of the fan sets.

Abstract: A precision grinding apparatus includes a grinding worm for precision grinding a case-hardened face gear. A shaper is first placed into contact with a face gear, to thereby shape a surface of the face gear into a plurality of face gear teeth. The shaper is then removed, and the face gear is case hardened. The grinding worm is disposed in a normal orientation to the case-hardened face gear and includes a spiral tooth extending along a perimeter of the grinding worm. The spiral tooth of the grinding worm is adapted to contact and precision grind the case-hardened gear. A dressing tool includes a protrusion for contacting the spiral tooth of the grinding worm, as the spiral tooth contacts and precision grinds the case-hardened face gear. The dressing tool thus maintains the shape of the grinding worm to within a desired tolerance range.

Abstract: A shaft deflection controller includes an input driveshaft adapted for inputting power from an engine. The input driveshaft includes an axis of rotation and a spur pinion at an end of the input driveshaft. The axis of rotation of the input driveshaft changes, relative to a frame, with deflections of the input driveshaft. Two face gears are adapted for meshing with the spur pinion of the input driveshaft. A flexible shaft stabilizing mount includes an inner sleeve portion and a mounting flange. The inner sleeve portion includes a base portion connecting the inner sleeve portion to the mounting flange and a plurality of cage spring members. The mounting flange is connected to and concentric with the inner sleeve portion. The flexible shaft stabilizing mount controls the deflection of the input driveshaft by applying forces onto the input driveshaft, which tend to resist changes in the alignment of the axis of rotation of the input driveshaft. The flexible shaft stabilizing mount is connected to a rigid frame.

Abstract: A conversion access gearset includes a first bevel gear, which is connected to a wing cross shaft leading from the proprotor drive train path to the second turbine engine. A second bevel gear is connected to a main transmission input shaft, which is adapted for driving the proprotor. A bevel pinion receives power from the turbine engine, and drives both the first bevel gear and the second bevel gear. An input pinion is connected between the turbine engine and the bevel pinion, and several idler gears are connected between the input pinion and the bevel pinion. A helical gear is connected between the several idler gears and the bevel pinion. The main transmission input shaft is connected to a main transmission input pinion, which is located on the main transmission input shaft opposite of the second bevel gear. The main transmission input pinion receives torque from the main transmission input shaft, and a torque-splitting device splits the torque received from the main transmission input pinion.

Abstract: A concentric face gear assembly includes a first face gear having first face gear teeth and second face gear having second face gear teeth. At least one input pinion contacts both the first face gear teeth and the second face gear teeth, and at least one idler pinion contacts both the first face gear teeth and the second face gear teeth. The first face gear is adapted for directly driving a rotor, but the second face gear is not adapted for directly driving a rotor. The load carried by the first face gear includes the force needed to drive the rotor. Since it does not drive a rotor, the second face gear does not comprise a web or spline attachment and is therefore lightweight. Both the first face gear and the second face gear include thrust bearings, which are located radially outwardly of the first face gear teeth and radially inwardly of the second face gear teeth.