Helicopter low-speed yaw control

US5209430A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• John C. Wilson · Rochester, US
• Cynthia A. Crowell · Glenrio, US
• Henry L. Kelley · Newport News, US

Key dates

• Filing date: Nov 7, 1991
• Grant date: May 11, 1993
• Expiry date: Nov 7, 2011

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B64C2027/8245
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A system for improving yaw control at low speeds consists of one strake placed on the upper portion of the fuselage facing the retreating rotor blade and another strake placed on the lower portion of the fuselage facing the advancing rotor blade. These strakes spoil the airflow on the helicopter tail boom during hover, low speed flight and right or left sidewards flight so that less side thrust is required from the tail rotor.