An Expedition Helicopters Aerospatiale AS 350 B-2, registration C-GSSS, powered by a Honeywell LTS-101-700-D engine, was substantially damaged during an emergency autorotation landing following an in-flight engine shutdown. According to the Transportation Safety Board of Canada,the helicopter was transporting a drilling crew from a base camp about 80 miles east of Big Trout Lake, Ontario, to a drill site, when, while in cruise flight, an uncommanded left yaw was experienced. The pilot performed an autorotation and the helicopter landed hard in shallow water near the shore of a lake. The helicopter was substantially damaged, but all occupants exited the helicopter safely and waded to shore. The Transportation Safety Board of Canada is investigating this event. For further information, contact: Mr. Ross Penden, Investigator-In-Charge Transportation Safety Board of Canada Tele: +1-204-983-2847; Mobile +1-204 771-6999 Email: ross.peden@tsb.gc.ca This report is for informational purposes and contains only information obtained for or released by the TSB.