We all know the tragic story of the Titanic. However, did you know that we can see a piece of the boat, “the big piece”, a part of the hull, exposed in Las Vegas ? This would not have been able to happen without our special PRONAL solution: underwater lift bags.

The story of the Titanic

On the night of April 14-15, 1912, the Titanic struck an iceberg and sank off the coast of Newfoundland. The White Star Line boat was leaving Southampton, England, and was supposed to sail to New York after a stopover in Cherbourg and Ireland. Its sinking killed nearly 1500 people. 

The wreck of the ship was discovered in 1985, 73 years after its sinking. It was found by a Franco-American scientific team, 600 kilometers from Newfoundland. The Titanic sank 3900 meters from the surface. The RMS Titanic company decided to go in the marine cemetery, and take back the wreck to the surface.To do this, they have partnered with Ifremer, the French institute of seabed research.

Their goal is to retrieve the “big piece” that comes from the debris field nearly 800 meters wide, scattered between the two main sections of the wreck. This piece is trunk-shaped and measures about 6 by 7 meters. That is the width of 2 cabins.

This organization already worked with Pronal for our underwater parachutes. Therefore, they decided to contact us again for this adventure in 1996.

PRONAL Underwater lift bags

The goal of this expedition was to raise to the surface the largest part of the Titanic still in condition, a fragment of the hull weighing 15 tons. 

RMS Titanic asked us for a special unit system. Therefore, Pronal realized a custom-made product, inflatable underwater lift bags with flexible tanks: “We designed a product derived from our flexible tanks but completely modified with lifting skirts, handles and an orange color that shows up well underwater” explains Mr. Nalpas, at the time CEO of the company. 

Those lift bags look like buoys: there are 6 in total, of 20 cubic meters. In total, this lifting system could lift up to 22 tons.However, they are inflated with diesel oil in order to play with its density: diesel oil is lighter than water, which allows the tanks to generate a lifting force.

These buoys are therefore empty, hooked to heavy chains allowing the solution to sink to the seabed.

When the system is hooked to the “big piece”, a hose fills the tanks with diesel fuel, allowing them to return to the surface. 

Mr. Nalpas simply calls this lifting system an “elevator”.

In this video you can see the strength of our products, as well as the big piece brought to the surface.


Therefore, those underwater lift bag brought part of the hull to the surface on August 10, 1998. Since the discovery of this wreck, about 5,000 objects have been brought to the surface. 

However, this is the only and largest piece ever brought up from the sea bed. 

This expedition was a historic success for the film and marine industry but also for Pronal. It was covered by French television, NBC and Discovery Channel. A small television studio was even built on board the Nadir (submarines). 

Today, scientists explain that the wreck of the Titanic will have completely disappeared by 2030. Indeed, buried at the bottom of the ocean for 110 years, the ship is devoured by bacteria and will be  dust in a few years. So why not try again before the Titanic disappears completely?

Would you like more information on this project?

Vous pouvez contacter nos experts qui sont adeptes de ce genre de projet pour avoir plus d’informations et être conseillé

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