For effective and efficient performance of wind turbines, components and systems should perform at a low risk with minimal downtime. To establish the impacts of wind turbine-components maintenance on downtime and failure risks, a six state Markov model was developed using the failure rates and downtimes information. The transition and maintenance rates at the lifecycle phases (introduction, maturity, ageing and terminal) together with those at maintenance and failure phases were determined using a calibrated survivability index whilst the transition rate probabilities were used in modelling the performance and failure risks probabilities at different maintenance intervals. The model was tested using failure rates and downtime information of wind turbine components obtained from literature and the results indicates that the model has practical applications for managing wind turbines. (C) 2016 Elsevier Ltd. All rights reserved.