The Army, twice as large as the other services combined with about 56,789 active duty personnel, consists of six infantry brigades, an air cavalry squadron and a combat service support brigade. The Air Force operates two main bases, one in southern region near Santo Domingo and one in the northern region of the country, the air force operates approximately 40 aircraft including helicopters. The Navy maintains three ageing vessels which were donated from the United States, around 25 patrol crafts and interceptor boats and two helicopters.