Italian army paratrooper Maresciallo Giovanni Pupillo, center, explains to U.S. paratroopers how to practice executing door exits on the mock door trainer at Aviano Air Base, before airborne operations onto Juliet drop zone in Pordenone, Italy, Sept. 12, 2017. The brigade is the Army Contingency Response Force in Europe. The soldiers are assigned to the 1st Battalion, 503rd Infantry Regiment, 173rd Airborne Brigade. Army photo by Davide Dalla Massara