SD speaks at AFA conference From left, Air Force Chief of Staff Gen. David L. Goldfein, Defense Secretary Jim Mattis, Secretary of the Air Force Heather Wilson and Air Force Association chairman F. Whitten Peters confer during the Air Force Association’s Air, Space and Cyber Conference in National Harbor, Md., Sept. 20, 2017. DoD photo by Air Force Tech. Sgt. Brigitte N. Brantley SHARE: Download: Full Size (1.77 MB) Tags: JIm Mattis, SecDef, AIR FORCE, Airmen Credit: Brigitte N. Brantley VIRIN: 170920-D-GO396-0090.JPG Photo Gallery