The unmanned aircraft were tried by the US military to see if they can transport heavy supplies over long distances, and to be thrown away after each use.
Logistic Gliders Inc. (LGI) tested two of their gliders, made of cheap plywood, the LG-1K model (can carry about 300kg) and the LG-2K model (700kg)
The gliders can be dropped from a helicopter or pushed out the back of a cargo aircraft. Military personnel could then potentially manage the glide via radio control or let the drones fly autonomously until a controlled crash takes place.
The LG-1K and LG-2K models are reportedly cheap to manufacture, costing as little as a few hundred dollars each. The low cost of the gliders makes them a lucrative tool for the military sector, and could prove cheaper than the current system of air-dropping supplies by parachute.
This is not the first time unmanned aircraft have been tested for delivery purposes. In the commercial sector, back in 2015 the US Federal Aviation Administration has granted permission to Amazon to use UAV for training and R&D.