A CH-47F Chinook helicopter from Task Force Iron Knights, 2nd Battalion, 501st Aviation Regiment, 1st Combat Aviation Brigade, 1st Armored Division, takes off from Roberts International Airport, Monrovia, Liberia, to conduct transportation mission in support of Operation United Assistance Dec. 9, 2014. Operation United Assistance is a Department of Defense operation in Liberia to provide logistics, training and engineering support to USAID-led efforts to contain the Ebola virus outbreak in western Africa. (U.S. Army photo by Sgt. Jose Ramirez, 1st Combat Aviation Brigade, 1st Armored Division Public Affairs/Released)