Soon, the U.S. Navy will lose another entire class of ships. These are the YTBs (Yard Tug Big), which are the military equivalent of the civilian tugs you see in any large port. The YTBs have been around for over a century. The last military ones built, in 1975, were about 110 feet long and displaced 350 tons. In the 1980s, the navy realized it would be cheaper to outsource the tug jobs (moving large warships and support ships into and out of docks, and moving barges of supplies around). For one thing, civilian tugs were more modern, and efficient. A navy tug had a crew of twelve, a similar size civilian tug had only four sailors on board. Despite the increasing breakdown rate of the remaining 30 tugs, the navy has not been able to scrape together the money to build new ones. If this is not done in the next 10-15 years, the existing ones will all be out of action and no YTBs will be available. This will cause problems in foreign ports, where you can't always depend on the locals to forget politics and just move the damn ships. In the United States, portions of some bases are highly classified, and getting civilian tug crews with the appropriate security clearances might be difficult.