VHA’s 206B/L main rotor blades were initially designed with two or three overlapping abrasion strips covering the the leading edge. The inboard and middle abrasion strips were made from roll-formed stainless steel; the outboard tip nickel abrasion strip is electroformed in-house at VHA.
These abrasion strips are non-structural components of the main rotor blade assembly and serve to protect the underlying composite material from impact and erosion damage. The abrasion strips are designed to remain installed and in service even after sustaining damage due to erosion, impact, or cracking as long as no underlying void or debond has occurred (in the case of an impact).
While the main rotor blades’ stainless steel abrasion strips are the same material from the same manufacturer as the abrasion strips on our UH-1 tail rotor blades, which have flown up to 2,500 hours with no cracking, some customers are reporting cracks on their VHA main rotor blades within the first 1,000 hours of flight. The interim solution for these customers is to apply a polyurethane tape across the cracks as specified in Customer Service Specification 501 (CSS-501).
