Each new model flies in its own way. Previously, I was in a hurry to launch a new model into the sky... Now I am definitely abandoning this idea in favor of planning. I trim and move the battery to achieve near-perfect planning. On the first flight, I smoothly step on the gas. Very rarely, unexplained cases occur: the model takes off vertically at 20-30 m, turns around and flies down completely uncontrollably. There were 2 such cases in different places with different models. When I assemble a model, I constantly control the center of gravity by moving the control mechanisms along the fuselage.