Design, elaboration of an engineering project and manufacture covers for Wind Turbines - Full redesign of top lids: - Calculation by finite elements of the different load situation. - Substantial improvement of the tightness over the design of the original serie. - Reduction of the cost and time of lids assembly and disassembly during maintenance operations. - Adaptation to the existing design. - Logistic adaptation of the new design to road transport. - Design of anchoring systems to existing machines. - Improvement of anti-slip system. - Manufacturing following ALSTOM maintenance planning.