Titanic expedition: Here's what it was like inside the 'Titan' submersible

CTV National News: Cost of finding a missing sub Judy Trinh reports on the early estimated multimillion-dollar cost to help locate the missing Titan submersible.

Ocean enthusiasts interested in the "Titan" submersible expedition were not signing up for a deep-sea joy ride, but rather an intense exploration of the ocean in a tight, enclosed space, according to descriptions from those who've taken the trip.

The submersible created by U.S. company OceanGate was used on expeditions to the Titanic wreckage site off the coast of Newfoundland. Testimonials on the company's YouTube channel describe the "real risk" involved for the citizen scientists on board and the captain.

According to OceanGate, the Titan submersible was made of carbon fibre and titanium and 6.7 metres long. It weighed 9,525 kilograms and could reach a depth of up to 4,000 metres. The submersible could also carry a payload weight of 685 kg and contained approximately 96 hours of "life support" for a crew of five.

Photos and videos from the expedition show crew members in a seated position inside the submersible with various laptop monitors and tech equipment surrounding them. The tube-like vessel had no standing room and just enough space for passengers to work on the mission at hand, with tasks including collecting data and inspecting the submersible.

The Titan could also get cold, according to former OceanGate mission specialist Colin Taylor, who says the lack of light in the depths of the ocean can make for frigid temperatures. OceanGate stated the vessel was equipped with "state-of-the-art lighting" to cut through the darkness of the water, but that the below-freezing temperatures combined with the materials of the submersible could make the Titan quite cold.

A video posted to the OceanGate's YouTube channel shows what the inside of the vessel looks like upon descent. Crewmembers are shown sitting closely together in the dimly lit submersible; most of the interior is illuminated with screen monitors. A separate video detailing the entire excursion also shows how dark the vessel could get, with just one circular window at the end of the Titan allowing in whatever sunlight was filtered through the ocean or from bioluminescent sea creatures.