Abstract: A recovery system and method for recovering a deployed vessel having a rotatable support coupled with a stored recovery assembly, including a release unit, line, deployment weight, and drag device on the deployed vessel. A recovery vessel can have a hoist with a coupling element, such as a grapple. For recovery, the recovery assembly can be deployed from the deployed vessel. The drag device can assist in floating and/or maintaining a taut line, especially when the vessel is downwind of the drag device. The coupling element from the recovery vessel can couple with the taut line. Once coupled, the recovery vessel can raise the coupling element with the line, which can rotate the rotatable support to a lifting position above a center of gravity of the deployed vessel. The recovery vessel can then lift the deployed vessel vertically out of the water to a storage position.

Abstract: The disclosure includes a recovery system and method for recovering a deployed vessel having a rotatable support coupled with a stored recovery assembly, including a release unit, line, deployment weight, and drag device on the deployed vessel. A recovery vessel can have a hoist with a coupling element, such as a grapple. For recovery, the recovery assembly can be deployed from the deployed vessel. The drag device can assist in floating and/or maintaining a taut line, especially when the vessel is downwind of the drag device. The coupling element from the recovery vessel can couple with the taut line. Once coupled, the recovery vessel can raise the coupling element with the line, which can rotate the rotatable support to a lifting position above a center of gravity of the deployed vessel. The recovery vessel can then lift the deployed vessel vertically out of the water to a storage position.

Abstract: The invention concerns an assembly for installation of an underwater structure on the sea floor, said sea floor being covered with particles capable of being driven in suspension in the water above said sea floor, the mounting of said underwater installation capable of being implemented by an underwater robot driven by propulsion means, said propulsion means being capable of displacing the sea floor water and said suspended particles around said installation; said assembly comprising means (22, 26) for covering said sea floor surrounding said installation with a protective blanket (10) adapted to confine said particles on said sea floor.

Abstract: A method and a device for installing a sub-sea riser for an offshore operation, between a base installation disposed on the sea bed and a sea installation protruding above the base installation. The sub-sea riser is provided with a first end and a second end. The method comprises the following stages in the following order: a) the first end of the riser is joined to the sea installation; b) the sub-sea riser is deployed; c) the second end of the riser is guided towards the base installation; d) the second end is coupled to the base installation by releasing the second end and the efforts of the recoil force exerted on the base installation are transferred; e) the second end and the base installation are connected to each other.

Abstract: The invention concerns an assembly for installation of an underwater structure on the sea floor, said sea floor being covered with particles capable of being driven in suspension in the water above said sea floor, the mounting of said underwater installation capable of being implemented by an underwater robot driven by propulsion means, said propulsion means being capable of displacing the sea floor water and said suspended particles around said installation; said assembly comprising means (22, 26) for covering said sea floor surrounding said installation with a protective blanket (10) adapted to confine said particles on said sea floor.

Abstract: A method and a device for installing a sub-sea riser for an offshore operation, between a base installation disposed on the sea bed and a sea installation protruding above the base installation. The sub-sea riser is provided with a first end and a second end. The method comprises the following stages in the following order: a) the first end of the riser is joined to the sea installation; b) the sub-sea riser is deployed; c) the second end of the riser is guided towards the base installation; d) the second end is coupled to the base installation by releasing the second end and the efforts of the recoil force exerted on the base installation are transferred; e) the second end and the base installation are connected to each other.