Using non-standard M2.5 hexagonal screws can a stable connection between the Printed Circuit Board and the lever arm. Adopting integrated Printed Circuit Board wiring and equipped with strengthen 5um composite Printed Circuit Board, electrical adjustment and other wiring faster and safe. The new is lowered the installation position of the motor and raised the Printed Circuit Board position, making the center of gravities of the new four aircraft lower and more stable. Optimization the to provide ample installation space for various flight controlled Equipped with gimbals mount, the boom adopts inward and lateral inclination which can make the aircraft more stable in roll and pitches directions and flexible in rotate.