Advance Testing of Lightning Protection Schemes for Composite Main Rotor Blades (Helicopter),
Abstract
The choice of composites, with their structural and aerodynamic advantages, for helicopter main rotor blades is briefly discussed along with some of the difficulties associated with their design, manufacturing and testing. This paper is concerned with the necessity for lightning and erosion protection for the blade's leading edge and the desire for early evaluation of projected design schemes. Attention is drawn to the lengthy lead time between the designing of a blade and the arrival of suitable, expensive tooling required to examine an actual blade specimen. A technique has been developed which satisfies both the designer and the accountant. A blade is imagined to be cut, spanwise, from root to tip through the trailing edge and spar rearwall. The blade is then opened out like a book. If care is taken with the manufacture of the flat test specimen various lightning protection schemes can be evaluated well in advance of prototype blade specimens. The bulk of this paper examines a selection of protection schemes and the effect of varying the engineering tolerances of erosion shield assembly and the extent of damage so caused. The information gained through this work enabled blade design to be finalized well before actual blade specimens became available for test. Testing showed close correlation to the results of their flat counterparts. Work has now progressed into the modelling and testing of flat panels representing complex blade planforms that do not immediately appear to lend themselves to this technique. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1983
- Accession Number
- ADP002210
Entities
People
- M. J. Heseltine