Call Sign Extortion 17: The Shoot-Down of SEAL Team Six, is a 2015 non-fiction expose, written by best-selling author and former U.S. Navy JAG Officer Don Brown, about the 2011 Chinook shootdown in Afghanistan of a United States Boeing CH-47 Chinook helicopter. It is published by Rowman & Littlefield Publishing Group, through its Imprint, Lyons Press. In the shoot-down, 30 Americans lost their lives, including 17 U.S. Navy SEALs, most of whom were members of SEAL Team Six, officially the United States Naval Special Warfare Development Group.