How engineers are making planes that run on batteries and not hydrocarbons Every modern airplane is built twice. First on screens. Then in metal. And that’s not a figure of speech. Airbus put it bluntly: "We're essentially manufacturing each aircraft twice — once in a machine-driven environment and then again in a human-driven one." It sounds simple — create a version on the computer, test it for problems, correct them and then build the real thing. But what really takes place in those digital prototypes? Engineers don't just test designs. They break them. Deliberately. Repeatedly. Thousands of times. A physical test costs about 100 times as much as a virtual one. So, before they cut a single length of metal, teams run their aircraft through simulated hurricanes, lightning strikes to its body, the impact of birds on its wings and vibrations intended to simulate hard knocks that would really be dangerous to test out with a real airplane. When something finally takes flight? It has already endured far more abuse than most airplanes will ever see in service.