And now we have the Silent Venus, a next generation "last mile" drone expected to be production ready next year.
https://www.undefinedtechnologies.com/p ... -rendering
The ionic cat is out of the bag and his name is Townsend.Since Thomas Townsend Brown discovered propulsion generated by asymmetrical electrodes in 1921 there had not been a significant break-thru that allow generation ion propulsion to levels that made it possible to develop VTOL crafts in atmospheric conditions. Our all-electric drone powered by ion propulsion, with minimum noise signature and zero carbon emissions, uses innovative physics principles to generate noise levels below 55 dB.