Steeplejack
Definition: a worker who builds or maintains tall buildings, working at great heights
Why I Looked It Up
In Empire, there was a discussion about the first attempt to moor a zeppelin to the top of the Empire State Building.
On the 150th floor balcony, three men from the crew waited to grab a rope trailed by the aircraft. A steeplejack was poised with a sharp knife to sever the line if it got tangled.