REPORT OF FIRST YEAR'S ACTIVITIES (15 JUNE 1952 - 15 JUNE 1953)

Abstract

Improved helicopter performance is being sought by the application of boundary-layer control (BLC) to helicopter rotor blades. The possible benefits of BLC include an increase in the maximum lift coefficient (and stalling angle of attack) of the rotor blade to delay the stall of the retreating blade and thereby permit a higher forward speed of the helicopter, and a reduction of the profile drag of the rotor blade so as to reduce the power required for a given lift. Wind-tunnel studies were made on the use of single suction slots located in the forward portion of the top side of the airfoil. Results showed that the stalling angle of the NACA 0015 airfoil could be extended from the normal 14 to about 31, with a correspondingly large gain in maximum lift coefficient, with the use of reasonably low suction quantities. Wind-tunnel data indicated the possibility of using BLC in an intermittent manner to permit great savings in air pumping power.

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Document Details

Document Type
Technical Report
Publication Date
Jul 13, 1953
Accession Number
AD0018197

Entities

People

  • Sam Hinton

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircrafts
  • Airfoils
  • Airframes
  • Boundaries
  • Boundary Layer
  • Boundary Layer Control
  • Drag
  • Drag Reduction
  • Helicopter Rotors
  • Helicopters
  • Layers
  • Military Research
  • Rotary Wing Aircraft
  • Steady State
  • Suction Slots
  • Wind Tunnel Tests
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Logistics and Supply Chain Management.
  • Systems Analysis and Design