Kopp-Etchells Effect on rotor blades

[stephenb]

I was sent these images last night and decided to investigate them. I have spoken to a friend who's son is serving in the US armed forces and they are aware of this phenomenon also.

There are many references to the Kopp-Etchells effect on the internet and it appears to be a common occurance in sandy environments.

Here is a more in-depth article at www.military.com
(http://www.military.com/forums/0,15240,198227,00.html)
I thought this might be of interest to some of the aviation folk on IIS.

[Omaroo]

Amazing, huh!

[JohnG]

Helicopters are notorious for building up Static Electricity in humid/dusty conditions, you soon learn as a crewman, not to touch a winch cable before it has hit the ground and earth's, I can asure you, you can't feel your arms and legs for ages and I have ended up on my backside a few times :D.

Have done a lot of night winches and have seen this effect on only a couple of occasions.

Cheers

[Ric]

That's a pretty amazing effect.

Could be a bit scary though if you don't actually want to give your position away to the enemy.