Schottel to provide propulsion systems for seven more Navy vessels

Schottel Usnavy Dockingtug 01

(SPAY, Germany) — Schottel has again secured several orders to provide propulsion systems for U.S. Navy vessels. This additional order of five workboat docking vessels and two YTL tugs – all of which are to be built at the Modutech Marine Inc. yard in Tacoma, Wash. – represents a continuation of the strong relationship between the parties.

The main propulsion for each workboat docking vessel consists of a Schottel SRP 150 azimuthing unit with fixed-pitch propellers with a diameter of 3.4 feet and an input power of 335 kW. These are driven by diesel engines. The rudderpropellers will be equipped with the new high-efficiency nozzle SDC40, which combines compact design and high propulsion efficiency.

Each of the Robert Allan-designed YTL tugs will be propelled by two Schottel rudderpropellers type SRP 270 FP with a propeller diameter of 6 feet and an input power of 970 kW. They will be powered by diesel engines. With this propulsion system, the vessels achieve a free running speed of approximately 10 knots and an expected bollard pull of 32.7 tonnes.

The design for the U.S. Navy will also include updates to suit new EPA Tier 4 engines and associated systems while also featuring extensive fendering above and below the waterline to handle U.S. Navy surface ships, submarines and barges. The 63-foot tugs are essentially configured as “day boats." Nevertheless, they also provide accommodation for a crew of up to four people.

Construction of the lead tug is to commence in 2020.

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By Professional Mariner Staff