A Ukrainian helicopter veers left while providing aerial support to ground troops during a water gap crossing demonstration during Rapid Trident 2019 in Yavoriv, Ukraine, Sept. 20, 2019. RT19 is an annual, multinational exercise occurring from Sept. 13-28, 2019, which involves approximately 3,700 personnel from 14 nations, that supports joint combined interoperability among partner militaries of Ukraine and the United States, as well as Partnership for Peace nations and NATO allies.