 The first jet aircraft to enter service was the Lockheed T-33 trainer to fight the growing insurgency; the US supplied four jets in 1963, two in 1964 and two more in 1965.In 1965, the US also supplied four armed Sikorsky UH-19B helicopters, the first military helicopters in Central America.In 1967 the FAG acquired five Bell UH-1B and UH-1D helicopters from the US to reinforce its helicopter force.