What is the tallest building in America?



It's One World Trade Center, the Council on Tall Buildings and Urban Habitat's Height Committee announced Tuesday, settling a debate between New York and Chicago over the tallest-building mantle.





Critics had said the 408-foot spire atop the 1,776-foot One World Trade is an antennae and should not be counted. Without it, the building would measure 1,368 feet, or 83 feet shorter than Chicago's 1,451-foot Willis Tower.

But architects for the yet-to-be-opened One World Trade Center say the spire is part of the building’s overall aesthetic appeal.

The council agreed. "That crowning structure is never to be added to and never to be taken away," Antony Wood, the council's executive director, told reporters.

The symbolic height of One World Trade Center, 1,776 feet, also played a roleQ:

Why can't Pratt & Whitney make RD-180 engines on their own?

From Wikipedia:

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.[3] 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.[4]

From my understanding, Prat & Whitney have technical plans and documentation, why they still can't manage to produce engines independently?

A:

In something as