Operator reports he was on a plane and was heading in a southerly direction towards Frenchman's Island.  Operator stated he was clear of the danger markers when he struck something submerged underwater.  This resulted in the lower part of the lower unit to break away from the boat.  There was no damage to the hull of the boat.  The boat was towed by Brewerton Fire Department to Oneida Shores Park.
Constantia                    