 Alpine 4 Holdings Inc OTCQB:ALPP said its Vayu Aerospace Corporation subsidiary has successfully demonstrated its G1 and US-1 airframes to several customers in the energy and mining industries. Alpine 4 also noted that, in all cases, both the G1 and US-1 drones demonstrated superior flight time along with an agility to work in tight spaces, such as power lines, while covering a great distance between energy generation locations. 