Reference:  http://www.daviddarling.info/encyclopedia/W/wind_turbine_UFO.html 

On January 4, 2009 a wind turbine suffered unusual damage.  The turbine is one of 20 on a wind farm in Conisholme, England.  The damage is unusual because it cannot be explained.  Several witnesses reported strange lights hovering and an explosion which took the form of an octopoid during which the turbine lost a 66 foot blade and had another twisted and mangled.

The mysterious lights gave witnesses the idea that it was caused by an extra terrestrial ufo.

The owner of the turbine farm, Ecotricity, said the damage was “unique” and had no explanation.  They are doing an investigation and have sent to the broken blade to Germany for testing.

Metal fatigue has been put forward as an explanation for the damage and ice has also been put forward.  But these theories ignore the witness accounts of the strange lights in the area and the octopus form of the explosion that caused the damage. 

The shape of the octopus is a clue. 

Those who study cavitations know that cavitating bubbles will take on this form under certain circumstances.  Here is a picture of a cavitating bubble in the form of an octopus.

 Reference: CAVITATIONAL MICRO-PARTICLES:  PLASMA FORMATION MECHANISMS

By IOAN BICA

http://www.infim.ro/rrp/2005_57_1/Ioan_Bica.pdf

So the turbine was struck by lightning, but not regular lightning, but what is commonly known as ball lightning.  Ball lightning, which is just a larger cavitating bubble, will drift on wind currents and will be attracted to a static electric field such as one generated by a wind turbine farm.