Rescuers race against the clock to find missing sub bound for Titanic

ViewRescuers are racing against the clock to locate a missing submersible bound for the Titanic wreckage before it's too late. 

The carbon-fiber submersible named the Titan, part of a mission by OceanGate Expeditions, is carrying a pilot, a renowned British adventurer, two members of an iconic Pakistani business family and...