NASA moves a step closer to supersonic passenger flights | CNN
www.cnn.com
A new study by NASA’s Glenn Research Center has looked at the possibility of supersonic passenger jets. Its “high-speed strategy” is mooting commercial flights that travel at up to Mach 4 – over 3,000 miles per hour – starting with transoceanic routes.

In July, Lockheed Martin completed the build of NASA’s X-59 test aircraft, which is designed to turn sonic booms into mere thumps, in the hope of making overland supersonic flight a possibility. Ground tests and a first test flight are planned for later in the year. NASA aims to have enough data to hand over to US regulators in 2027.

    • keeb420@kbin.social
      41·
      1 year ago

      yeah i experienced a sonic boom once, obama came to seattle and a small private plane accidentally entered the restricted airspace, that was one too many. even if its lessend its not gonna be pleasant to be under.

      • Ryumast3r@lemmy.world
        6·
        1 year ago

        They’re promising a perceived 75 dB level, equivalent to the volume of a dishwasher. Sonic booms are normally about 110 dB or about a jackhammer or a rock concert

        And it’s not like you’d hear it all the time, just once in a while and only if you’re in the flight path.

        • keeb420@kbin.social
          41·
          1 year ago

          will it reduce the air pressure difference on the ground? i was in a building and it moved. i felt it. sound is only one problem.

          Overpressure
          Sonic booms are measured in pounds per square foot
          of overpressure. This is the amount of the increase
          over the normal atmospheric pressure which surrounds
          us (2,116 psf/14.7 psi).
          At one pound overpressure, no damage to structures
          would be expected.
          Overpressures of 1 to 2 pounds are produced by
          supersonic aircraft flying at normal operating altitudes. Some public reaction could be expected between 1.5 and 2 pounds.
          Rare minor damage may occur with 2 to 5 pounds
          overpressure.
          As overpressure increases, the likelihood of structural
          damage and stronger public reaction also increases.
          Tests, however, have shown that structures in good
          condition have been undamaged by overpressures of
          up to 11 pounds.
          Sonic booms produced by aircraft flying supersonic at
          altitudes of less than 100 feet, creating between 20 and
          144 pounds overpressure, have been experienced by
          humans without injury.
          Damage to eardrums can be expected when overpressures reach 720 pounds. Overpressures of 2160
          pounds would have to be generated to produce lung
          damage.

          https://www.nasa.gov/centers/dryden/pdf/120274main_FS-016-DFRC.pdf

          • Ryumast3r@lemmy.world
            3·
            1 year ago

            Yes, they would reduce the overpressure. By how much I’m not sure, but that’s part of the research.

        • KevonLooney@lemm.ee
          43·
          1 year ago

          They’re promising

          I guarantee it will be louder than that. Unless the flight path is directly over a senator’s house or an historic golf club (where donors play), it will be too loud.

          Literally make the flight path over the richest part of town or I won’t believe it.

          • Ryumast3r@lemmy.world
            31·
            1 year ago

            NASA has no control of flight paths. The FAA also doesn’t specify sonic-boom allowed flight paths. They just outright ban it (with a few exceptions) for any boom that could reach anywhere in the US.

            FAA also doesn’t want to deal with people complaining about sonic booms like they did back in the 50s when this all started (they received tens of thousands of complaints) so they have an interest in making sure NASA lives up to their promises.