While there are always accidents with any advanced and deployed technology, with windmills it's not an accident.  Reports (albeit anecdotal) coming out of the lowlands indicate that windmills get bored late at night, at least when the the winds have decreased below cut-out... and tend to go on rampages, attacking anything that moves.  Particularly the younger windmills, as discussed in a current diary here.  Preliminary investigations have shown alcohol to be involved, though the turbines deny this.  We've begun to see younger turbines moving their yaw bearings below the tower joint, exposing their variously colored "yaw drives."  It is apparently these turbines, the so-called "rebel punks," who are alleged to be the perpetrators.

I understand there are at least two scripts on this theme floating in Hollyweird, one modeled after "Killer Tomatoes."  

Preview is your friend.

"Life shrinks or expands in proportion to one's courage." - Anaïs Nin