Kopp-Etchell Effect

[JakesF14]

Something interesting...

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"

Abrasion in sandy environments

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.

[Hagar]

Very interesting.

Michael Yon has documented the effect, and has named it after two U.K. soldiers who died there. "Kopp-Etchells"

According to Wikipedia the effect is named "in honor of Cpl. Benjamin Kopp, and Cpl. Joseph Etchells, fallen American and British soldiers respectively".

[DaveSims]

Just to point out, as these pictures came up in another forum, these photos were taken using night vision.  The effect seen here is real, but not visible to the human eye. 

[Hagar]

[quote]Just to point out, as these pictures came up in another forum, these photos were taken using night vision.

[expat]

Cough already posted cough

Kopp-Etchell

Matt

[JakesF14]

Missed it  :-) Thanks Matt!