Low-Radar-Cross-Section OH-6A Helicopter Tail Rotor Blade

Abstract

The design, fabrication, and testing results of a low-radar-cross- section (LRCS) filament-wound composite tail rotor blade for the OH- 6A helicopter are reported herein. Two full- scale blades and four 12-inch-long blade sections were fabrica-ted during the program. The blades and blade sections were fabricated of Kevlar 49 roving/epoxy. The blades and blade sections all had sheets of microwave-absorbent materials laminated integrally with the windings to reduce the radar signature of the composite. The program objective of developing an LRCS BLADE WITH STRUCTURAL CHARACTERISTICS SIMILAR TO THE CURRENT METAL OH-6A HELICOPTER TAIL ROTOR BLADE USING NON- METALLIC AND RADAR-ABSORBENT MATERIALS WAS MET. The four blade sections were used to evaluate the radar reflection characteristics of four different radar shielding configurations. These blade sections were tested for radar signature, and the raw test data were sent directly to the Army. The Army's evaluation of radar test data, along with FSI fabrication and structural analysis findings, formed the basis for select-ing the radar shielding configuration to be used in the full-scale blades. The composite blade was found to be very similar in weight, stiffness, and natural frequency to the metal blade in addition to being considerably more durable (resistant to handling damage). The design concept is new for filament-wound composite blades; fabrication was found to be relatively simple and amenable to low-cost blade production.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1974
Accession Number
AD0781564

Entities

People

  • Dale Abildskov
  • Sam Yao

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aerodynamic Configurations
  • Aircrafts
  • Airframes
  • Center Of Gravity
  • Composite Materials
  • Helicopter Rotors
  • Materials Processing
  • Mechanical Working
  • Modulus Of Elasticity
  • Radar Cross Sections
  • Radar Signatures
  • Resins
  • Resonant Frequency
  • Shielding
  • Spars
  • Tail Rotors
  • Test And Evaluation

Readers

  • Aerodynamics.
  • Aerospace Engineering
  • Radar Systems Engineering.