More details emerge in future Dutch submarine programme
Recently French shipbuilder Naval Group and the Swedish-Dutch combination Saab-Damen released more information about their proposals for the Dutch Walrus class replacement.
Naval Group plans to offer the Dutch Defence Materiel Organisation (DMO) a design based on the new nuclear submarine Barracuda, Naviesworldwide.com learnt during a visit in Cherbourg, France . This SSN is currently built by Naval Group in Cherbourg.
Naval Group was successful with another Barracuda derivative, the Shortfin Barracuda, in a tender for the Australian navy. Now Naval Group has designed another conventional submarine, this time for The Netherlands.
There are no details known about the French offer, but Naval Group’s choice to offer a design based on the Barracuda, means that they have a large submarine in mind. Presumably larger than the 2,000 ton Scorpene. The five French submarines of the Barracuda class have a subsurface displacement of 5,300 tons, much more than the Walrus class which boast a mere 2,800 tons.
The French submarines have a length of 99.5 metre. The design for The Netherlands is expected to be much shorter.
Also Saab and Damen offer a design based on a submarine which is currently being built: the A26.
Naviesworldwide.com learnt during a recent visit to Malmö and Karlskrona more details. Saab and Damen designed a submarine with a displacement of 2,900 tons, a length of 73 metres and a diameter of 8 metres.
While the 5,300 tons Barracuda has only 4 torpedo tubes (and no VLS), the Saab-Damen offer has six of them plus a Multi Mission Lock. This additional tube has a diameter of 1,5 and is meant for all kinds of large and small drones, and for up to six divers or special forces including equipment.
The submarine’s fore ends is designed as a multifunctional area, where of course torpedoes and missiles can be stowed but also drones. However, the area -not quite spaciouis on the current Walrus class- can also be used as a Special Forces command centre or as a briefing room.
Like the A26 this design includes a Stirling AIP-motor. The Stirling uses ordinary diesel and liquid oxygen. Both are available in ports and also liquid oxygen can be loaded quickly. The engine is a combustion engine, but there are no explosions in place like a petrol or diesel engine. Instead, the engine works with a gas that expands by heat (the combustion) and shrinks again later by cooling. The engine is very quiet due to the absence of explosions. Moreover, the Stirling engine hardly vibrates. Naviesworldwide.com has seen a running Stirling engine which is meant for the first A26, with a coin standing on its side.
To reduce heat and vibrations in the engine room all engines have a casing.
Apart from Naval Group and Saab-Damen, TKMS (Germany) and Navantia (Spain) also offered designs to DMO. At the end of the year two companies will be chosen to go on to the next stage. In 2021 a contract with one of the competitors will be signed.