A single-tilt-rotor VTOL airplanes have a tiltable rotor attached to an elongated
power pod containing the collective and cyclical pitch mechanism, and transmission.
The power pod is pivotably attached to a base that is slidably mounted on a pair
of slotted guide beams attached on top of the roof of the fuselage. The guide beams
run longitudinally from the front of the aircraft to past the center of gravity
(CG) of the aircraft in order to transport the power pod from the front section
to the center section when converting from the horizontal cruising mode to the
VTOL mode. In the horizontal cruising mode, the power pod perched horizontally
on top of the fuselage front section with sufficient clearance for the rotor to
rotate in front of the aircraft. Upon transitioning to the VTOL mode, a telescopic
actuator is used to pivot the power pod vertically while a cable-winch system is
used to move the entire power pod and base assembly rearwardly to stop at the center
of gravity of the aircraft, and vice versa, thus allowing the power pod to travel
significantly rearward and forward as required for proper balancing of vertical
lift as the power pod pivots 90 degrees during transition from VTOL mode to the
cruising mode. A single piston engine, or a single or pair of turbofan engines,
mounted slightly to the rear of the CG, have drive shafts that can be clutched
and mated onto respective receiving shaft from the transmission within the power
pod in order to power the tiltable rotor. The engine is also attached to a propeller
for horizontal propulsion, or if turbofan engines are used, jet thrust is generated
for horizontal cruise. A small anti-torque rotor or ducted fan toward the tail
of the aircraft is mechanically coupled to the engine via a drive shaft to provide
the necessary side-way thrust to overcome the main rotor's torque. In the horizontal
cruising mode, the tiltable rotor is allowed to windmill slowly at a minimum rotational
speed necessary to maintain the integrity of the rotor blades. The same propulsion
principle can be applied to VTOL airplanes having more than one tiltable rotor,
thereby can potentially increase the speed, range and reliability of current twin-wing-mounted-tilt-rotor
aircraft. A pair of high-aspect-ratio wings on both sides of the fuselage provide
highly efficient lift during cruising flight with very little induced drag. Conventional
horizontal and vertical tail planes are used for directional stability in the cruising mode.