Accession Number:

AD0780720

Title:

Rotor Blade Treatments to Minimize Electrostatically Generated Noise on the HLH Helicopter

Descriptive Note:

Corporate Author:

BOEING VERTOL CO PHILADELPHIA PA

Personal Author(s):

• DeRosa, R.
• Solak, J.

Report Date:

1974-05-01

Pagination or Media Count:

68.0

Abstract:

A laboratory investigation was undertaken to evaluate the severity of precipitation-static noise to be expected on the Heavy Lift Helicopter HLH low-frequency systems, and to define the requirements of techniques for noise elimination on the HLH. This investigation, using a 125th scale model of the HLH and actual proposed rotor-blade panel samples revealed the need for RFI protection on the HLH. Recommendations were made to install P-static dischargers on the HLH rotor blades, and the optimum number and location of these dischargers was discussed. Noise reduction afforded by various rotor-blade-coating systems was also investigated and reported. A recommendation was made for a particular coating system, based on noise-reduction and surface-resistivity measurements.

Descriptors:

• *HELICOPTER ROTORS
• ELECTRICAL GROUNDING
• ELECTRICAL CORONA
• STATIC DISCHARGERS
• PROTECTIVE COATINGS
• ELECTROSTATIC CHARGE

Subject Categories:

• Helicopters
• Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE