Federal investigators say a sudden downdraft caused a helicopter to crash while filming a car on an Audi test run in Colorado.

The National Transportation Safety Board says a downdraft forced the helicopter into Pikes Peak mountain in September. The Gazette newspaper in Colorado Springs says the NTSB probe found the pilot couldn't "power out" of the wind because of the high altitude.

The pilot landed the helicopter near the road, where it rolled onto its left side. He suffered minor injuries but the three passengers were unharmed.

The helicopter was carrying a crew filming a driverless Audi on the road to the mountain's 14,110-foot summit.

Audi has said the test drive was part of a project with Stanford University, which helped create the technology for the driverless vehicle.


Information from: The Gazette, http://www.gazette.com