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Kopp-Etchells Effect, really cool!

Featured Replies

When helicopters pass through

dust storms, contact of the particles with the rotating blades

produces either sparks or static electricity.

The phenomenon has been

observed during combat operations in

Afghanistan ; Michael Yon has documented the effect, and has named it

after two U.K. soldiers who died there. "Kopp-Etchells"

 

When operating in sandy

environments, sand hitting the moving rotor blades erodes their

surface. This can damage the rotors; the erosion also presents

serious and costly maintenance problems.

The abrasion strips on

helicopter rotor blades are made of

titanium, which is very hard, but less hard than sand; so when a

helicopter is flown near to the ground in desert environments

abrasion occurs, and at night there is a visible corona or halo

around the rotor blades, caused by the sand hitting the titanium and

causing it to spark and oxidize.

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/monthly_06_2011/post-2828-130810230463_thumb.jpg

/monthly_06_2011/post-2828-130810230466_thumb.jpg

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image004.jpg.7834dbc7c2675780d465d5f35fc63872.jpg

image003.jpg.1b2d38b18220e35832a69e8db1bfce0f.jpg

  • Author

When helicopters pass through

dust storms, contact of the particles with the rotating blades

produces either sparks or static electricity.

The phenomenon has been

observed during combat operations in

Afghanistan ; Michael Yon has documented the effect, and has named it

after two U.K. soldiers who died there. "Kopp-Etchells"

 

When operating in sandy

environments, sand hitting the moving rotor blades erodes their

surface. This can damage the rotors; the erosion also presents

serious and costly maintenance problems.

The abrasion strips on

helicopter rotor blades are made of

titanium, which is very hard, but less hard than sand; so when a

helicopter is flown near to the ground in desert environments

abrasion occurs, and at night there is a visible corona or halo

around the rotor blades, caused by the sand hitting the titanium and

causing it to spark and oxidize.

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