Noise is a sound that humans do not want. In this study, Based on the Rotax 912 engine, which is most commonly used in Korea, we will look at noise and thrust changes by changing the propeller blade angle by 1 degree for the two-blade Sensenich Propeller and the three-blade Wrap drive Propeller. Through this, we want to check which part of the propeller angle produces the least noise and the least thrust loss for each propeller, and propose a propeller operation plan in a noisy area based on the value.

In this paper, Fly robot with electric power, a kind of Unmanned aerial vehicle (UAV), is considered as an autonomous hovering platform, capable of vertical lift-off, landing and stationary hovering. This aircraft has four rotor and DC motors of electrical Power, which is capable of Omni-direction for indoor application. In the earlier days of vertical flight experimentation developers looked at the intuitively easy control functionality of 4 rotor designs. But we need to obtain design method of suitable structures and adequate components because the existing prototypes of 4 rotor-craft don't analyze the propeller, motor characteristic and propose a methodology to optimize this system. In design of propeller, experimental results show that thrust and power are relatively efficient at a pitch angel of 20 degree. To the conclusion, the design method and optimization method of the propeller, motor, frame, Blimp, which are the main design elements of the blimp type 4 rotor craft, were studied to optimize the existing Blimp 4 rotor craft body design method.