The Chantiers de l’Atlantique in Saint-Nazaire have devised a whole system for facilitate and stabilize launching and recovery small vessels or drones under 12 meters from vessels over 60 meters. Whether they are shipowners who should be able transfer staff on offshore platforms (wind or oil), whether they are exploration cruise lines who make their passengers jump in small canoes, or the military who are increasingly using underwater drones for monitor cables where to find mines or explosivesthe Worksites system “meets a need” explains the naval architect Arnaud Benoist, “because there are a lot of accidents“.
A gantry, a U-shaped basket held by straps: a kind of automatic elevator
Ten years that the Chantiers are working on this idea, the studies began 5 years ago, the Chantiers are now at the final phase of sea trials which end on Thursday. In back of the ship (here for the barge tests): a gantry, 46 tons of steel, as found in the port of Saint-Nazaire except that it is attached to the ship, it can lift up to 20 tons. Then there is this basket or this cradle U-shaped, whose arms are adjustable, which will accommodate the boat with a system of lock, straps and winchthe craft or drone is back on the ship or down on the water. A bit like a elevator, all you have to do is press a button.
– Helen Roussel
It works even with waves over 2 meters
The main innovation is this system “heave compensation, that is to say that the cradle and the boat marry the undulations of the sea and that the boat is only raised once it is at the top of the wave”, explains Damien Groussin of the company Nov BLM based in Carquefou. A device that absorbs shocks and thereforeavoid collisionand which is not afraid of the swell, the tests were carried out successfully on waves over 2 meters.
No more jumping ship to join the boat ou to crochet the drone by hand to retrieve it on the lateral side of the ship, “which was very risky“. The Shipyards who tested their discovery for 3 weeks present it as a world first. “We already have customers, industrialists, French but also foreign who anticipate the development of military marine drones and who are very interested because the launching and especially the recovery are obviously heavy stakes”.
– Helen Roussel