There's a lot of effort going into researching ways to make booms from SSTs quieter. NASA's has a low-boom research program trying to turn the booms into "gentl

There's a lot of effort going into researching ways to make booms from SSTs quieter. NASA's has a low-boom research program trying to turn the booms into "gentle thumps" by changing the shape of plane's shockwaves [0]. Lockheed are building the X-59 for demonstration flights for the program. [0] https://www.nasa.gov/X59 https://www.nasa.gov/X59