RAPID APPLICATION. LASTING PROTECTION.

Modern wind turbines operate in harsh conditions, with blade tips reaching around 300 km/h where raindrops strike like hammer blows. Over time, this impact erodes the leading edge, creating pits and gouges that disturb airflow, increase drag by up to 86% and reduce lift by as much as 6%. Even moderate erosion can reduce annual energy production (AEP) by 3–5%, costing tens of thousands of euros per turbine each year and accelerating structural wear, especially offshore where blades are longer, tip speeds are higher, and access is costly.  

Historically, rope access technicians have handled leading edge repairs, sanding and rebuilding damaged areas. But they face a materials tradeoff: thin coating layers (approx. 600um) are easy to apply yet often show early erosion, while thicker shell systems or shields deliver better protection but require custom designs, complex alignment, and multiple steps that are hard to perform efficiently on ropes. For operators, this means choosing between simple, short-lived fixes or durable but costly, time-consuming solutions — neither of which are ideal when maintenance demand is growing faster than the supply of skilled technicians. 

In many fleets, this tradeoff shows up directly in maintenance planning. Coating-based repairs tend to require more frequent return visits, adding inspection and rope access days that consume limited weather windows and maintenance budgets. Shell-based systems, on the other hand, can tie up teams on a smaller number of blades, making it harder to keep up with erosion repair work during limited seasonal windows. As operators look to standardize LEP strategies across multiple turbine platforms and sites, the need for a solution that combines robustness with field efficiency has become increasingly clear. 

Sika’s latest leading edge protection (LEP) system, SikaForce®-860 LEP, is designed to end this tradeoff. Based on a 2-component polyurethane, it is applied as a thick, elastic layer — typically a minimum of 1.5 mm at the leading edge, fading down the chord — to absorb impact energy and resist crack propagation. The material’s non-sag, trowelable rheology lets rope access teams apply it by spatula on vertical or overhead surfaces without dripping, shaping a smooth aerodynamic profile that delivers rain erosion performance comparable to traditional shells. 

At the heart of the system is Sika’s “Curing by Design” technology, which decouples work time from curing speed. Technicians have a long open time to mix, place, and profile the material, followed by a fast through-cure at room temperature, minimizing downtime and allowing more blades to be treated within a weather window. SikaForce®-860 LEP remains flexible down to -35°C, offers high tear resistance, and is formulated for UV and weather stability, ensuring long-term performance in cold climates and offshore sites. 

From a field perspective, the system fits directly into established rope access workflows, and the spatula-based application means no complex jigs or rigid shells are needed on ropes. Surface preparation, mixing, application, shaping, and curing follow a straightforward sequence that can be completed within short windows, making it well suited for both onshore and offshore fleets where leading-edge erosion is one of the most frequent repair categories. The system is designed for manual repairs but can also be used by automated repair robots. 

Today, dozens of turbines in the United States are already spinning with the help of SikaForce®-860 LEP, proving its durability and handling in real-world conditions. By combining shell-like longevity with coating-like application, the solution helps operators stabilize AEP, extend maintenance intervals, and make better use of limited technician resources — moving the wind industry forward one blade at a time. 

• Leading edge damage is among the most frequent blade repair needs, particularly offshore

• Blade tip rotation speeds near 300 km/h expose edges to extreme rain impacts

• Erosion can increase drag by up to 86% and reduce lift by 6%

• Even moderate erosion can cut AEP by 3–5%, equal to tens of thousands of euros per turbine annually  

• 2-component polyurethane LEP applied by spatula, non-sag and rope-access friendly 
• Thick, elastic layer (~1.5 mm at the edge) for superior damping and shell-like rain erosion performance 
• Long open time with fast room-temperature through-cure to reduce downtime 
• High tear resistance, UV and weather stable down to -35°C 
• Already in service on dozens of turbines in the US