https://www.youtube.com/watch?v=DOWDNBu9DkU https://www.youtube.com/watch?v=DOWDNBu9DkU Saw saw this video the other day. Check out the drone around 13:55 rega

https://www.youtube.com/watch?v=DOWDNBu9DkU https://www.youtube.com/watch?v=DOWDNBu9DkU Saw saw this video the other day. Check out the drone around 13:55 regarding noise and rotor design. The whole video is worth a watch though. The company is zipline which is mentioned in a comment above.