Granted Patent
Utility
US 4,306,837 · App. 06/032,763
Bearingless tail rotor for helicopters
Inventors:
Vas H. Brogdon, Cecil E. Covington, Richard E. Wheelis
Patented Case
View Patent ↗
Granted: Dec 22, 1981
Filed: Apr 24, 1979
Inventors
Vas H. Brogdon
Cecil E. Covington
Richard E. Wheelis
Assignee (at issue)
Textron Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.