Two rhinos at the Kuzikus Nature Reserve in Namibia, photographed by drone. When the U.S. military needed to identify mines in a dangerous valley in Afghanistan, aerial-imagery specialist Tudor Thomas helped build a plane-based system to map it. Back in 2013, similar systems cost the military and its contractors one to five million dollars, Thomas says--and that didn't even include the cost of the plane. "It's hard to comprehend how much was getting spent just to make a simple aerial image," he says. The experience sparked an idea for a business: mapping by drone.