Hardware of software failure?
Unfortunately for Airbus, the £4.3m Zephyr surveillance drone encountered "clear turbulence" while climbing away from the airstrip which caused it to tumble out of control
Does it mean that the software was not able to control the movement of the plane in the turbulence? I wouldn't be surprised, flying a glider is a lot more difficult than a normal plane. However there might be some missing, not so small, details in the article. It would be interesting to know whether at least the structure is strong enough to sustain some turbulences or it is fragile as an old zeppelin.