Accession Number:

AD0781564

Title:

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

Descriptive Note:

Final rept. Mar-Dec 1973

Corporate Author:

FIBER SCIENCE INC GARDENA CA

Personal Author(s):

Report Date:

1974-04-01

Pagination or Media Count:

71.0

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 rovingepoxy. 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 Armys 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.

Subject Categories:

  • Helicopters
  • Active and Passive Radar Detection and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE