It would be hard to anti-noise the Rotodyne because it literally had small jet engines on the end of each rotor - which was why it so incredibly loud in VTOL.<p>I can&#x27;t find actual noise figures for it, but I suspect it wasn&#x27;t all the much louder than some modern jet liners. But jet liners land at out-of-city airports, and the whole point of the Rotodyne was that it could land in the middle of a city - and you&#x27;re not going to get certification for that for a plane that can be heard miles away.<p>I&#x27;d guess it was unbearably noisy inside the cabin too.<p>Here&#x27;s a sales video, with vintage cheesy music and equally vintage British accents:<p><a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=u4Z1UnRZDyo" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=u4Z1UnRZDyo</a>