A small armada of specialised planes and vessels is taking part in the frantic search for the tourist submersible missing in the North Atlantic with five people aboard who are running out of air.
They include submarine-detecting planes, teleguided robots and sonar listening equipment to help scour the ocean for the sub, which had been due to visit the wreckage of the Titanic.
Here is a look at this flotilla.
Air search at first
At the start of the search on Sunday, US and Canadian military planes were sent to the site of the Polar Prince, the mother ship that deployed the submersible called Titan hours earlier.
Several C-130 planes are scouring the surface of the sea visually and with radar. Canadian P-3s, maritime patrol planes, have deployed sonar buoys to listen from the surface of the ocean.
A Canadian P-8, a submarine-chaser that can detect objects under water, has also joined the search effort.
It was Canadian P-3s that detected underwater noise yesterday that provided the first glimmer of hope that the people on the Titan might still be alive, the US Coast Guard said.
Read more:
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Ships in place
Deep Energy, a ship that lays pipe on the seabed, has rushed to the scene and sent robots under water.
A Coast Guard photo shows the ship at sea, its deck packed with huge pieces of heavy equipment.
Three other ships arrived on the scene this morning.
The Canadian Coast Guard contributed the Atlantic Merlin, which has an underwater robot, and the John Cabot, a ship with side-scanning sonar capabilities to capture for more detailed images.
The third is the Skandi Vinland, a multi-purpose vessel dispatched by the Norwegian oil services company DOF. It has deployed two underwater robots.
A small armada of specialised planes and vessels is taking part in the frantic search for the tourist submersible missing in the North Atlantic with five people aboard who are running out of air.
A vessel called L'Atlante, a research ship belonging to France's National Institute for Ocean Science, is scheduled to arrive this evening.
It boasts a robot called Victor 6000, which has a 8km umbilical chord and can dive more than far enough to reach the site of the Titanic wreck on the seabed, more than two miles (nearly four km) down.
The US Coast Guard says four other vessels are expected to arrive, including the Canadian military ship Glace Bay, which features medical staff and a hyperbaric chamber used to treat people involved in diving accidents.
