This is NASA’s first large-scale, piloted x-plane (or experimental aircraft) in more than three decades, and its goal is to reduce the loudness of a sonic boom to more of a sonic thump. When the long, slender jet transitions to supersonic speed, it will make about as much noise a car door closing, and since it will be flying 940 MPH at 55,000 feet, that could be essentially inaudible.

NASA will test the X-59 over select US communities to gather feedback, as it has done with the F/A-18 Hornet aircraft over Galveston, Texas. Those tests will help establish new rules for commercial supersonic air travel over land.

NASA will begin by conducting ground tests on the Mod II to prepare for the project’s next phases, which will include taxi and, eventually, flight tests. It’s not entirely clear when those will take place, but the Mod III and IV configurations of the plane will have wings unlike the current iteration. When a flight test does happen, it will make history as the first crewed X-plane in two decades.

X-57 Project Manager Tom Rigney said:

“The X-57 Mod II aircraft delivery to NASA is a significant event, marking the beginning of a new phase in this exciting electric X-plane project. With the aircraft in our possession, the X-57 team will soon conduct extensive ground testing of the integrated electric propulsion system to ensure the aircraft is airworthy. We plan to rapidly share valuable lessons learned along the way as we progress toward flight testing, helping to inform the growing electric aircraft market.”

NASA will share anything it learns about the vehicle’s electric propulsion system and about the process of achieving airworthiness to industry players and regulators. It ultimately hopes to help develop certification standards for electric aircraft, including urban air mobility vehicles (or what people are calling “flying cars“) capable of vertical takeoff and landing.