RedactedNarrative: Pre Accident Unknown 
   
  Vessel A with two persons on board were out on the main body of the lake sailing in the late afternoon.  Only the passenger was wearing a life jacket.  
   
  High wind speeds with intermittent high gusts were being experienced  when the operator turned into the wind to take down the main sail.  The tiller was locked at that time with a tiller tamer.  A heavy gust of wind flipped the boat onto it's side while the cabin door was still open causing the vessel to take on water very quickly.  The vessel then began to sink and the operator was forced to hold onto the life vest of the passenger. 
   
  The vessel then sank leaving the passenger and operator on the water.  The depth of water in the area was between 150 to 250 feet of water.  
   
  It is estimated from the report that the passenger and operator both were in the water for 20 minutes or more from the start of the incident.  They operator and passenger were both rescued by the park rangers in a patrol boat and hauled aboard using dive door access.  They were both transported to the hospital treated and released.