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.