SCHOTTEL RudderPropeller

Powerful, reliable, precise – for 70 years, the SCHOTTEL RudderPropeller has proven itself as a universal all-rounder in a wide variety of ship designs and areas of operation. The 360-degree steerable SRP combines maximum manoeuvrability and bollard pull with outstanding course stability during free sailing, providing powerful thrust in the chosen direction at all times. With more than 15,000 units installed, the SCHOTTEL RudderPropeller has become the leading propulsion system for vessels with low to medium speeds.


At a glance

  • Optimum efficiency for maximum manoeuvrability
  • High propulsion efficiency: lower operating costs and lower emissions
  • Precision positioning in DP operation
  • SCHOTTEL-exclusive features such as ProAnode, HTG, highly efficient nozzles, LeaCon or DuroVario
  • A whole range of configuration options enabling adaptation to diverse ship designs and individual requirements
  • Minimal maintenance effort, long-term availability of spare parts as OEM
  • Compatible with SCHOTTEL hybrid solutions (SYDRIVE-E and SYDRIVE-M)
  • Versatile: SRP-U, SRP-R, SRP-RT


Combination of propulsion unit and 360-degree steering

The SRP undergoes continuous development, offering customers state-of-the-art technology at all times. Today, the SCHOTTEL RudderPropeller is available in numerous variants covering a wide range of power sources, installation options and operation profiles. This great variety makes the SRP very versatile and able to meet special requirements (e.g. ice class up to FSIC 1AS/PC6 or propeller axles inclined at 98 degrees).

Developed and built in 1950 by Josef Becker, the founder of today’s SCHOTTEL Group, he quickly gained a foothold in the world of modern shipbuilding. The main distinguishing feature of the SRP is the combination of propulsion unit and azimuth steering. This makes a rudder superfluous and converts engine power into maximum thrust. The 360-degree steering of the rudder propeller means that the full propulsion power is available for manoeuvring.



SCHOTTEL Underwater Mountable RudderPropeller

As an underwater mountable version of the proven SRP, the SRP-U is designed for use in the most extreme conditions, such as those found in large drilling ships or offshore vessels of all kinds. The tried and tested method of mounting and dismounting on site underwater means that there is no need for a time-consuming stay in dry dock. In addition to all the advantages of the SCHOTTEL RudderPropeller, the SRP-U boasts simple and safe installation and ensures maximum dynamic positioning performance (DP) even in the most difficult sea conditions. In addition to the standard version, it is also available with an eight-degree inclined propeller shaft, which prevents any interference when installing several propulsion units or in special mounting conditions.

Technical data


SCHOTTEL Retractable RudderPropeller

Powerful, reliable, flexible – the SCHOTTEL Retractable RudderPropeller is the retractable version of the proven SCHOTTEL RudderPropeller. When retracted, the SRP-R functions as a fully 360-degree steerable propulsion unit. It combines maximum manoeuvrability, high propulsion power and precise dynamic positioning. The retractable thruster can also be equipped with an eight degrees inclined propeller shaft. This reduces the interactions between the propulsion units as well as between the units and the hull, resulting in even more propulsion efficiency.

Technical data Product page

Technical data

SRP in numbers


Special advantages of SCHOTTEL

In addition to developing new products and services, SCHOTTEL works continuously to optimize existing systems. Special features ensure that customers worldwide benefit from state-of-the-art solutions.

HTG: Innovative High Torque Gear

SCHOTTEL’s self-developed High Torque Gear (HTG) extends the service life of the gearbox, resulting in significant performance and safety gains. State-of-the-art milling and calculation methods are used to achieve shapes that enable a highly efficient, robust and safe gearbox with ideal gear geometry.

The HTG allows for example up to 15 percent more drive torque to be applied with the same bevel gear dimensions and in compliance with the same safety requirements of the classification societies.

LeaCon: reliable seal monitoring system

SCHOTTEL LeaCon is a sealing system certified by DNV which offers safe and reliable protection against contamination of the seawater by operating materials. Separate seals to the seawater and to the gearbox side ensure that both incoming seawater and escaping gear oil are collected in an intermediate chamber (LeaCon chamber). This effectively prevents water from entering the gearbox and, above all, oil from escaping into the seawater. With the connected vacuum system, the leakage fluid is automatically collected in a compact tank in the engine room.

Continuous monitoring

In addition to the leakage-free sealing against seawater, the LeaCon system is used to monitor the condition of the seals. It registers the amount of leakage collected and continuously checks the condition of the seals. This means that operational wear can be detected at an early stage and unscheduled maintenance can be avoided.

Complies with VGP regulations of the EPA

SCHOTTEL propulsion units equipped with the LeaCon sealing system comply with the VGP regulations of the US-American Environmental Protection Agency (EPA). There is no need to use bio oils (EAL).

ProAnode: increased corrosion protection

The German propulsion expert has set new standards for corrosion protection with the patented SCHOTTEL ProAnode: By moving the anodes from the outer surface to the outer cross-section of the nozzle, they are protected more effectively thus providing longer protection for the propulsion unit. There are also additional operational benefits, such as less flow disruption, resulting in fuel savings and lower operating costs.

Improved corrosion protection

To prevent the anodes from being knocked off by flotsam, ice or minor ground contact, they have been removed from the outer surface and integrated into the outer cross-section of the nozzle. Depending on their diameter and the anode material, these anodes can be integrated into the nozzle, allowing cathodic corrosion protection for up to five years. This means that fewer additional anodes are required on the hull or on other drive parts.

High-performance nozzles SDV and SDC

High-performance nozzles from SCHOTTEL are used in various types of vessels and applications to boost the propeller’s thrust force. Based on decades of propulsion expertise, SCHOTTEL VarioDuct (SDV) and SCHOTTEL CruiseDuct (SDC) feature impressively high outputs during free sailing and excellent bollard pull values. Part of this is the state-of-the-art technologies used to ensure the high performance characteristics of the nozzles.

The new nozzles are equipped with the exclusive ProAnode technology from SCHOTTEL as standard.

SCHOTTEL VarioDuct (SDV45)

The SDV45 combines proven higher efficiency during free sailing with excellent bollard pull values. In conjunction with optimally designed propeller geometries, the nozzle is able to fully utilize the outstanding performance values. Assuming the same propulsion power, the bollard pull is higher than the thrust of previous nozzles, while efficiency is significantly enhanced in the medium and higher speed range. This makes a major contribution to fuel savings.

The SDV45 is suitable for use in a wide range of operation profiles.

SCHOTTEL CruiseDuct (SDC40)

The SDC40 sets standards in terms of compact design and free sailing efficiency, thus also reducing operating costs compared to nozzles from other manufacturers. The high-performance nozzle is also characterized by optimally designed propeller geometries and outstanding performance features.

The nozzle has a particularly small outer diameter. This enables it to be optimally adapted to a wide range of ship designs and applications. At the same time, the high-performance nozzle is also suitable for conversions and upgrades with limited installation space. The SDC40 excels with the highest free sailing efficiency in transit at higher speeds. In addition, a higher maximum speed can be achieved.

Further nozzles are available on a project-specific basis.

DuroVario: fully integrated clutches

DuroVario allows SCHOTTEL to offer fully integrated clutches, optimally adapted to the propulsion properties of the respective propulsion system. Customers benefit from an above-average service life, which goes hand in hand with high service and spare parts availability. The compact and space-saving clutches also enable easier integration into a wide range of ship designs and straightforward installation thanks to plug-and-play setup. 

Depending on the type of clutch, the engine power is transmitted either by a simple on/off function or a convenient slipping function. The SCHOTTEL portfolio has the perfect solution for any application – all from a single source:


DuroVario-D is a standard clutch that ensures a safe and durable connection between the propulsion unit and the engine.


DuroVario-LS allows SCHOTTEL to offer a slipping clutch for occasional slipping at idling speed. This enables safe, durable and convenient connection of the propulsion unit to the engine.


SCHOTTEL DuroVario-S is a slipping clutch that combines permanent slipping with maximum comfort at engine idling speed.


DuroVario-PS is a performance-enhanced slipping clutch that allows FiFi operation (up to FiFi Class 1) without any additional changes to a ship’s design, while still allowing full manoeuvrability of a vessel with FP propellers.


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