Originally Posted by crewex
Wouldn't a tower crane have been less of an obstruction that the big unwieldly base of a sliding crane which looks like it obstructs a considerable amount of the oculus? The tower crane has the smallest foot print and can hover above the project. I'm just trying to come up with a "logical" or "economical" reason they would have switched.
The temp path entrance could be moved once the greenwich street entrances are all finished right?
While a tower crane is stationary and provides a smaller base than the sliding one, the lifting capacity is greatly reduced due to to the length of the boom. This crane started in the basement of the PATH hall, and with the ovular supports going in, now, there wouldn't have been enough swing distance.
Low lifting capacity=no heavy pieces of steel, such as the perimeter columns that are being installed now.
The movable one can move back and forth as it pleases, reducing the boom length, and since the portion where it is sitting happens to be an open area and the floor of the PATH hall, the swing distance isn't a factor, and it doesn't obstruct anything. It clears the two elevator wells they just placed at the easternmost portion of the site with no problem.
The entrances along Greenwich are for MTA's Cortlandt Street station, and connect only to the Oculus through the eastern box truss(which is accessible through an unbuilt mezannine level of the oculus), and parts of the WTC mall, I believe. Neither are near completed, so the temporary PATH entrance has to stay.