This is the tower after a 3 metre diameter (ten foot) turbine jumped off in reported 120 km/h winds in Palestine recently. The 1.5 inch inner pipe of the yaw bearing has clearly bent. COMET-ME will be using a larger pipe size for their yaw bearings in future. However this was the standard size that I specify in my Recipe Book.
Windspeed 120 km/h is only 33 m/s, which is not exceptional for us on Scoraig, but there could be other factors at work including turbulence. A high gyroscopic moment induced by a rapidly yawing rotor could be one. Anyway this is where this turbine failed and failures are useful lessons. That’s why I am sharing it on this blog.