13.

Besides the region’s great expanse, search efforts are also complicated by the depth at which the submersible may be located. “This is a complex case, and the Coast Guard doesn’t have all the resources to be able to affect this kind of rescue,” Mauger said. However, he said they are ready to “deploy all available equipment to the scene that can be used to locate the submersible whether it’s on the surface or down beneath.”

“Folks have been working around the clock to mobilize gear, to get it to the site, and to participate in the search for this submersible,” he concluded. 

Source: https://www.buzzfeed.com/alexalisitza/everything-you-need-to-know-missing-titanic-submersible