- The ships have many flat surfaces, particularly in their superstructures, where water collects and causes rust.
- Some of the ships sit on mud. Constant friction as they shift in their berths erodes their hulls.
- It was very difficult to fully clean the internal fuel tanks before the U.S. Navy loaned these ships to museums. Residues of fuel oil in the tanks create acidic conditions that corrode the tanks and the adjacent hull structures from the inside.
- The ships have a large number of intakes and discharge ports through their hulls. Although most of these were welded over when the ships were mothballed after World War II, each one is a source of leaks over the long run.
- Given wartime exigencies and the need for armor, the ships were constructed with dissimilar metals -- a circumstance that encourages corrosion.
- The assumption during design was that 2000 mostly idle sailors would be available to maintain the ships constantly. The museums don't have such a workforce to chip and repaint, to scrub the wooden decks, etc.
- Asbestos was widely used inside these ships.
- Getting repair equipment into the innards of the ships is difficult, expensive, and hazardous.
- Dry-docking these ships is also difficult, expensive, and hazardous. As New Yorkers saw with the Intrepid, simply getting them to move out of the mud and silt is a pain. There aren't many dry-docks that can handle ships of this size, and towing them through deep ocean waters to reach a dry-dock is another pain. The North Carolina would have to be towed at least as far as Norfolk. That's a far distance to pull 35,000 tons.
Wednesday, November 13, 2013
Preserving the USS North Carolina
A friend recently toured the USS North Carolina in Wilmington. As someone who considered becoming naval architect before I settled on electrical engineering, I've been through that ship and other museum warships many times. The North Carolina and others (Texas, Massachusetts, Alabama, Yorktown, etc) face an uncertain future, I'm sorry to say. These warships are over 70 years ago and face these problems:
at 2:15 PM