Dan Gryder has a vid on why this most likely happened. In summary the aircrafts emergency return to the departure airport turn onto final approach was with insufficient energy. To my simple high school physics mind aircraft have 3 types of energy. Kinetic, Potential, Fuel/engine. This aircraft had, 1 low kinetic, airspeed. 2 low potential, altitude. 3 low fuel, the ability to burn it with one engine inoperative. The inevitable sink happened with flaps and gear out, high drag resulting in the this terrible accident, it will happen every time. We can learn from this accident even if we fly simple single engine aircraft.