Patents Assigned to Bertelsen Inc.
  • Patent number: 4415131
    Abstract: A lightweight, man carrying aircraft including a skeletal fuselage assembly in combination with a primary arc-shaped lifting airfoil having variable camber, incidence angle, and pitching moment and a secondary stabilizing airfoil of a tubular, ring-like configuration. The arc-shaped primary airfoil is superior to traditional low speed airfoil forms due to its high aerodynamic efficiency, inherent design simplicity and strength. The ring-tail assembly, offering marginal aerodynamic lift, contributes significantly to the in-flight stability and safety of the aircraft. Both airfoil members are independently controllable and constructed of a fabric or like skin material which is fitted over a wing assembly and tensioned into an operable airfoil form by the aerodynamic forces of the air during flight. Typically, the wing assemblies are supported and maintained by a lightweight, tubular fuselage structure to which is affixed the propulsion system, control mechanisms and ground support assemblies.
    Type: Grant
    Filed: May 5, 1980
    Date of Patent: November 15, 1983
    Assignee: Bertelsen Inc.
    Inventors: William R. Bertelsen, William D. Bertelsen