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?

Is paying the cost of cut power lines part of the owner's
insurance package?

Chris Richardson > wrote in
:

> 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

On Sat, 24 Sep 2011 12:28:38 -0500, John Szalay wrote:

>
> 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

Thanks for taking the time and effort to do that. I had no idea
where such data could be located.

It would seem that only specialized helicopter applications
are prone to this kind of threat. Crop dusting is obviously
one, and power line inspection, which is presumably the job
of the chopper in this photo, would be another. Military
helicopters would need the protection of wire cutters as well.

But most helicopters take off from airports and quickly reach
altitudes that place them far above low-lying power lines and
cables.