Federal investigators say an unmanned Facebook aircraft's crash while on a landing approach at the end of its first test flight occurred when a wing broke because of wind gusts.
A National Transportation Safety Board final report on the June 28 crash on a runaway near Yuma, Arizona, says wind gusts were about twice as strong as the solar-powered Aquila's autopilot could handle.
CEO Mark Zuckerberg has said Facebook wants to use a fleet of high-flying aircraft to send internet signals to remote parts of the world.
The NTSB report released Friday says the aircraft was "substantially damaged" by the wing's structural failure and the ground impact but that there were no injuries or ground damage.
The wing damage occurred as the aircraft was about 20 feet off the ground.