Undefined claims 4.5-min flight for its “silent” ion-propulsion drone

The article is right to be skeptical of these claims. In the one flight video this company has shown, the drone isn't much more silent than propeller drones, and most of the video has music covering up the drone sounds. For how much they're hyping up the technology, one would think they would want to showcase how quiet it is. The other footage is a 3D render, and a presentation talking about their 2 successful flights and promising future plans.

The CEO doesn't inspire much confidence either. Seems like a snake-oil salesman fishing for investors.

This is what we used to call a "lifter". I did a project on them in high school. Very fun to do, since you use a very high voltage. Our physics teachers were very enthusiastic and helped us a lot, all the other teachers kept a very safe distance. Another fun aspect; because of their obscureness, doing any research on lifters led almost directly to ufo and anti-gravity websites. Based on what I saw on our lifter, generating enough lift to carry actual cargo would require a huge amount of power, or a huge leap in efficienty of their ion-generation. Interesting development, I'll keep an eye on them.