The appraisal committee listened to the R&D report of the R&D enterprise, the inspection conclusion of the inspection department and the opinions of the initial users, reviewed the technical data, watched the on-site operation demonstration of the prototype, conducted strict questions and extensive discussions, and considered that the 3ZD- 10A ultra-low altitude remote control flight plant protection machine developed by Hunan Bolian was based on the general technology of unmanned helicopters and aimed at the agricultural application requirements. It adopts aileron-free screw head, double push rod full-load tail rotor head, industrial fully sealed wet metal gear box, noise reduction and exhaust system matched with engine performance, all-aluminum alloy and carbon fiber composite fuselage, airborne power generation system, electronic stability and plant protection operation guarantee system, which has excellent pesticide spraying function, and can also be used for crop breeding and pollination, foliar fertilization, pest monitoring and other farmland operations, with reliable quality, stable performance and good user response, and meets Hunan local standard DB43/