Kopp-Etchells effect (30 photos)
In fact, the Kopp-Etchells Effect is a very new name. One American journalist decided to immortalize in this way the names of two American soldiers who died in July of this year in Afghanistan. Since this effect did not have a name, he named it after them (their last names were Kopp and Etchells). So here it is. The essence of the effect comes down to the fact that when landing or taking off in the desert, the helicopter blades and the sand that rises into the air collide. And if this happens in the dark, you can watch an amazing show.
