A rescue helicopter from the French Gendarmerie flies over the snow covered French Alps during a search and rescue operation near to the crash site of an Airbus A320 in the French Alps

A rescue helicopter from the French Gendarmerie flies over the snow covered French Alps during a search and rescue operation near to the crash site of an Airbus A320 in the French Alps

A rescue helicopter from the French Gendarmerie flies over the snow covered French Alps during a search and rescue operation near to the crash site of an Airbus A320, near Seyne-les-Alpes, March 25, 2015. French investigators will sift through wreckage on Wednesday for clues into why a German Airbus operated by Lufthansa’s Germanwings budget airline plowed into an Alpine mountainside, killing all 150 people on board including 16 schoolchildren returning from an exchange trip to Spain. REUTERS/Jean-Paul Pelissier