Abstract: A vertical takeoff and landing aircraft having at least three wings and at least six propulsion units, each of which are located radially from two adjacent propulsion units, by equal or substantially equal angles. The at least six propulsion units together being located symmetrically, or at substantially symmetric positions, about the approximate center of gravity of the aircraft, when viewed from above. A vertical stabilizer may or may not be employed. If no vertical stabilizer is employed, yaw control during horizontal flight may be achieved through differential thrust using the at least six propulsion units. Yaw control during vertical flight may be provided by a plurality of yaw control panels. Absent yaw control panels, yaw control during vertical flight may be provided using differential propulsion unit tilt angles.

Abstract: A vertical takeoff and landing aircraft having a fuselage with, preferably, three wings and six synchronously tilt-able propulsion units, each one mounted above, below, or on each half of the aforementioned three wings. The propulsion units are oriented vertically for vertical flight and horizontally for forward flight. Each propulsion unit comprises a propeller having a plurality of blades, where the pitch angle associated with the distal end of each blade and the proximal end of each blade are independently adjustable. As such, each of the propellers can be adjusted to exhibit a first blade pitch angle distribution optimized for vertical flight and a second blade pitch angle distribution optimized for forward flight.

Abstract: A vertical takeoff and landing aircraft having a fuselage with three wings and six synchronously tilt-able propulsion units, each one mounted above, below, or on each half of the aforementioned three wings. The propulsion units are vertical for vertical flight, and horizontal for forward flight. The aircraft wings are placed such that the rear wing is above the middle wing which is placed above the front wing. The placement of each of the propulsion units relative to the center of gravity of the aircraft about the vertical axis inherently assures continued stability in vertical flight mode, following the loss of thrust from any one propulsion unit. The placement of the propulsion units, viewing the aircraft from the front, is such that each propulsion units' thrust wake does not materially disturb the propulsion unit to its rear.