The Basler BT-67 aircraft operated by North Star Air, was conducting a series of flights between Pickle Lake Airport (CYPL), Ontario, and Fort Hope Airport (CYFH), Ontario, Canada. The purpose of the flights was to deliver 5940 L of diesel fuel per trip to the Eabametoong First Nation community, also known as Fort Hope. Before departing CYFH on the occurrence flight, the crew conducted the before-takeoff checklist, which requires the propeller automatic feathering system to be armed for takeoff; however, the crew did not arm this system. At approximately 01:40, the aircraft departed CYFH with the first officer acting as the pilot flying (PF), seated in the right seat, and the captain acting as the pilot not flying (PNF), seated in the left seat. Shortly after takeoff, the PF called for the landing gear to be retracted. The PNF then selected the gear up at approximately 200 feet above ground level (AGL). Both engines subsequently lost power simultaneously, and the flight crew executed a forced landing on Eabamet Lake, Ontario, in total darkness. The aircraft fuselage remained intact and immediately began to fill with water. The flight crew retrieved the survival kit, evacuated the aircraft via the main cabin door, and swam to shore. Once on shore, the flight crew started a fire to warm up. The fire was noticed by a patrolling officer of the Nishnawbe Aski Police Service, who responded and transported the flight crew to the nursing station at the Eabametoong First Nation Band Office for a medical assessment. Neither flight crew member was injured. The aircraft sustained substantial damage, but there was no post-impact fire. The aircraft remained floating in the water. Findings as to causes and contributing factors: 1. After lifting the landing gear control handle, with his left hand on or near the throttle quadrant, the pilot not flying may have inadvertently moved the fuel condition levers, cutting the fuel to both engines simultaneously.