The flying car is the key to unlocking a new era of low-altitude logistics and mobility, but such a novel mode of transportation will also bring about challenges we have never faced before. This article examines the human-machine interface (HMI) design of flying cars from an ergonomic perspective, identifying not only their unique characteristics and proposing design principles, but similarities to both automobiles and aircraft. Emphasis is placed on safety, noise reduction, and space optimization. Once the safety of flying cars is adequately ensured, our design focus will shift from safety to addressing personalized needs. It is worth exploring how to apply existing human-machine interface design guidelines to accomplish the ergonomics design of a flying car, and how to update existing design standards based on the challenges faced by flying cars. A survey reveals that safety, seating comfort, noise levels are the top concerns for potential users, highlighting the need for tailored HMI solutions in the future.