Voith has secured an order from the Spanish state-owned shipbuilding company Navantia to supply the complete propulsion package for their new submarine rescue ship BAM IS (Buque de Acción Marítima de Intervención Subacuática; Underwater Intervention Maritime Action Vessel), contracted by the National Armament Directorate (Dirección General de Armamento y Material; DGAM) for the Spanish Navy. The package consists of two electric Voith Schneider Propellers (eVSP) and three Voith Inline Thrusters (VIT) with integrated permanent magnet electric motors from ELIN Motoren GmbH, a subsidiary of Voith Turbo. ELIN Motoren produces electric motors and generators in small series and custom solutions for various industrial applications. The company specializes in markets such as marine, wind energy, plastics, tunnel and mining, oil and gas, plant construction and power plants.
The 90-m long ship is designed to carry out and support submarine deployments and is due to be delivered in 2026. The multifunctional and interdisciplinary tasks to be undertaken by the BAM IS will include diving missions and underwater operations, intervention and rescue assignments in the event of accidents, shipwreck search and location activities and underwater surveillance, including the protection of sunken cultural and archaeological artefacts.

The Spanish Navy’s decision in favour of the eVSP and VIT combination was made on the basis of extensive CFD (computational fluid dynamics) simulations and model tests that were carried out in close cooperation with the Hydrodynamics Team at Navantia and covered a wide range of criteria, from the ship’s resistance and the interaction between propeller and hull, through to dynamic positioning over a longer period. In particular, the superior performance of the eVSP combined with an optimised lower power requirement, were the decisive selection criteria over all other drive concepts in enabling the DP system to overcome the challenging sea conditions. [Ed.: DP or dynamic positioning is a computer-controlled system to automatically maintain a vessel’s position and heading by using its own propellers and thrusters.]

In order to be able to carry out its functional and interdisciplinary tasks in practice, the BAM IS must have such an extremely precise positioning system. State-of-the art drive technology provided by Voith is at the very heart of these systems: two powerful eVSP 32X6/285 at the stern, supported by three VIT 2000-1650H at the bow, deliver the propulsion needed to keep the ship in the required position for long periods in demanding sea conditions. Both drive technologies use an integrated permanent magnet electric motor from ELIN Motors.

“The extremely fast response time of the eVSP and VIT enables the Spanish Navy’s submarine rescue ship to perform at a high level at all times in providing accurate dynamic positioning and excellent manoeuvrability, which clearly surpasses that of comparable propulsion concepts,” said Michael Rommel, head of sales & application management at Voith.

In addition, the eVSP, in particular, has excellent hydroacoustics, and it is expected to generate reduced noise emissions underwater. Further benefits of the eVSP include an integrated roll stabilization system, which provide a noticeable improvement both in comfort and in the working and operating conditions on board the vessel.
“We are very proud that we have succeeded in meeting the extremely high requirements of the Spanish Navy to their utmost satisfaction and have been awarded the order. This is further proof of the competitive advantage that we have currently secured through the perfect combination of eVSP and VIT,” noted Ricardo Rodriguez, manager sales & customer service
Marine at Voith Turbo Spain.