Chris Richardson wrote in
news
On Fri, 23 Sep 2011 21:49:26 -0400, Glen Wattman wrote:

In this photo, the top and bottom "wire cutter" blades are
nicely visible. Their function is to cut any power lines
that the helicopter may accidentally fly through.

Does anyone have any figures on how many such accidents
occur in the US on a yearly basis?


a very quick NTSB database shows 6545 incidents involving "wires" from
1969 to date.. If you really interested you can inspect all of those..
;-)

quick look at some, many involve crop spray operations