How about one of the authors talking about a credit-card sized device supplying 100 watts to quad-coptors using liquid fuel and staying airborn for 16+ hours. (

How about one of the authors talking about a credit-card sized device supplying 100 watts to quad-coptors using liquid fuel and staying airborn for 16+ hours. (https://youtu.be/lDxJsa8miNQ?t=3202 https://youtu.be/lDxJsa8miNQ?t=3202)