Here's the entire process of using a Phantom 4 drone to measure stockpiles with Stockpile Reports. Here are the links mentioned in this video:
• AirMap for Drones: https://itunes.apple.com/us/app/airma...
• Map Pilot: https://itunes.apple.com/us/app/map-p...
• FAA Website: http://www.faa.gov
• Purchase a Phantom 4: http://amzn.to/2aNP85U