Under RD AMROSS, Pratt & Whitney is licensed to produce the RD-180 in the United States. Originally, production of the RD-180 in the US was scheduled to begin in 2008, but this did not happen. According to a 2005 GAO Assessment of Selected Major Weapon Programs, Pratt & Whitney planned to start building the engine in the United States with a first military launch by 2012. This, too, did not happen. In 2014, the Defense Department estimated that it would require approximately $1 billion and five years to begin US domestic manufacture of the RD-180 engine.
From my understanding, Prat & Whitney have technical plans and documentation, why they still can't manage to produce engines independently?