page_title: Kopp–Etchells effect
section_title: Consequences
hierarchical_section_title: Kopp–Etchells effect / Consequences
caption_attribution_description: English: A U.S. Marine Corps MV-22 Osprey assigned to Special Purpose Marine Air-Ground Task Force-Crisis Response-Central Command (SPMAGTF-CR-CC) stages on a hasty landing zone during a tactical recovery of aircraft and personnel (TRAP) drill at an undisclosed location in Southwest Asia, Nov. 16, 2015. SPMAGTF-CR-CC is ready to respond to any crisis response mission in theatre to include the employment of a TRAP force. (U.S. Marine Corps photo by Lance Cpl. Clarence Leake/Released)
context_page_description: The Kopp–Etchells effect is a sparkling ring or disk that is sometimes produced by rotary-wing aircraft when operating in desert conditions, particularly near the ground at night. The name was coined by photographer Michael Yon to honor two soldiers who were killed in combat; Benjamin Kopp, a US Army Ranger, and Joseph Etchells, a British soldier. Both were killed in combat in Sangin, Afghanistan in July of 2009.
  Other names that have been used to describe this phenomenon include scintillation, halo effect, pixie dust, and corona effect.
context_section_description: The erosion associated with the Kopp–Etchells effect presents costly maintenance and logistics problems, and is an example of FOD.
  Sand hitting the moving rotor blades represents a security risk because of the highly visible ring it produces, which places military operations at a tactical disadvantage when trying to remain concealed in darkness.
  The light from the Kopp–Etchells effect can interfere with the pilot's ability to see, especially when using night vision equipment. This may cause difficulty with landing safely, and produce spatial disorientation. With repeated exposure, the Kopp–Etchells effect could damage night vision gear.
caption: The Kopp–Etchells effect creates a halo around the rotors of a MV-22 Osprey in this long-exposure photograph.
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