...officials are working to get a remotely operated vehicle that can reach a depth of 6,000 meters (about 20,000 feet) to the site as soon as possible.

The 5-person submersible, named Titan, is capable of diving 4,000 meters or 13,120 ft. “with a comfortable safety margin,” OceanGate said in its filing with the court.

but...after looking up on Wikipedia

...a wreck that lies over 12,000 feet (3,700 m) below the surface...