Patents by Inventor James E. Duh

James E. Duh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Rotor blade assembly with high pitching moment airfoil section for a rotary wing aircraft
    Patent number: 7547193
    Abstract: A main rotor blade assembly with a high negative pitching moment airfoil section having a pitching moment coefficient beyond (more negative than) ?0.035 at Mach Numbers below 0.80 and a blade taper of 1:5 or greater.. The main rotor blade preferably limits blade torsional bending and an aft loaded tip airfoils to approximately ‘no more’ than that of conventional effective rotor blade designs based on conventional tip airfoil sections.
    Type: Grant
    Filed: July 22, 2005
    Date of Patent: June 16, 2009
    Assignee: Sikorsky Aircraft Corporation
    Inventors: Robert Moffitt, James E. Duh, Charles Berezin