Effect of Rotor Blade Root Cutout on Vertical Drag

Abstract

Tests were conducted to determine the effect of rotor blade root cutout on the vertical drag of winged rotorcraft. Rotor thrust and torque were measured on isolated model rotors with blade root cutouts of 10 and 50 percent radius and were compared to the values obtained when a model fuselage and wings of three different planform areas were located below the rotor disc. Vertical drag was recorded on all airframe configurations with both sets of root cutout blades. The test data revealed a decrease in vertical drag for all airframe configurations when tested with the blades having 50 percent root cutout. The largest vertical drag reduction was measured for a small wing located high on the fuselage. The 4 percent figure of merit penalty due to 50 percent blade root cutout of the isolated rotor was diminished to 2 to 3 percent for most conditions when the reduction in vertical drag was taken into consideration.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1970
Accession Number
AD0877174

Entities

People

  • Sebastian J. Cassarino

Organizations

  • United Technologies Corporation

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Aircrafts
  • Airframes
  • Army Aviation
  • Coefficients
  • Downwash
  • Dynamic Pressure
  • Figure Of Merit
  • Fuselages
  • Helicopter Rotors
  • Helicopters
  • Measurement
  • Moment Of Inertia
  • Planform
  • Rotary Wing Aircraft
  • Telescoping Rotors
  • Test Equipment

Readers

  • Aerospace Engineering
  • Mathematics or Statistics