To evaluate the concepts the da Vinci I prototype was built and tested and the lessons learnt from the first aircraft were incorporated into da Vinci II featuring two 23m long rotor blades powered by propellers located at the tip and driven by the pilot.是什么意思_To evaluate the concepts the da Vinci I prototype was built and tested and the lessons learnt from the first aircraft were incorporated into da Vinci II featuring two 23m long rotor blades powered by propellers located at the tip and driven by the pilot.在线翻译_英语_读音_用法_例句