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Caister's New Lifeboat 2004

Development & Construction.

Some extracts have been taken from a full report on Dutch Lifeboat operations here!

Background to the designer and his fight to develop a water jet powered offshore lifeboat.

Initial design work for this Caister Lifeboat was carried out by David Stogdon MBE, who had inspected lifeboats during most of his working life, who better to produce a design for a new advanced lifeboat? In the late 70s David Stogdon commanded a joint project between the Dutch and the RNLI the first prototype of the Medina class as it was named was launched in 1979 and showed great promise. The second Medina, the Countess Mountbatten of Burma, had an enclosed wheelhouse for crew protection. Self-righting capacity was provided by the air in the watertight wheelhouse. The K.N.Z.H.R.M. showed great interest in the Medina as a possible replacement of her wooden motor lifeboats of the Eierland class (these were launched from the beach by launching carriages and watertight tractors). In 1981 the Northern Dutch lifeboat organisations signed a 'Memorandum of Understanding' with the RNLI, in which the promise for support (including financial support) to the development of a water jet driven Medina with a draught of about 0.60 m. was written down. The 'North' preferred water jet propulsion and asked for the 0.60 draught because the boats had to be launched from the beach and operate in the shallow waters of the Wadden.

Water jet propulsion.
In 1983 the RNLI built a prototype. The boat showed excellent manoeuvrability at low speed and stopped just as well. (The water jet was a bit similar to an aircraft turbojet.) The water was sucked in through the inlet at the bottom and pumped out by an impeller pump through the outlet nozzle with enormous force. Steering was done by moving the nozzles vertically by helm and so deflecting the water flow to starboard or port. Reversing was done by horizontally moving deflectors or 'buckets'. When full ahead the bucket was lifted free from the jet flow. In neutral the jet flow was bent vertically downwards and in reverse in forward direction to the bow. The boat always had thrust. By moving the helm the boat could be turned even when neutral. At high speed steering was done by using the helm. Manoeuvring at low speed was done by using the buckets ( in combination with or without the helm), that were independently handled by levers. With her two water jets the boat could easily be turned on her axis and even be sailed sidewards.) The boat could be landed on the beach easily and without damage. She was able of a speed of 26 knots.

Development of the vessel continued up until 1993, by which time several problems remained to be overcome, mainly to do with engines and corrosion problems which proved difficult to resolve at the time. Concerns about shock loadings for both the crew and the boat during heavy weather remained. However with todays modern construction, powerful light weight diesels and epoxy paints, the major hurdles were overcome for boats like the Valentijn 2000 which includes specially developed seating.

Medina-project abandoned by the RNLI.
By 1993 the RNLI had already abandoned the Medina-project. According to Gerry Keeling, International Development Manager of the International Lifeboat Federation Secretariat it was difficult to find out the exact reasons for the abandonment. To his understanding there were technical problems associated with the size and weight of the diesel engines which were available at that time. In one or another way the Medina had not been the boat for the RNLI. Gerry underwrote a lifeboat always was some kind of compromise: 'Fully planing hulls had a lot of surfaces to glide over the water and produced great speeds for very little power. Unfortunately, such hull types could not operate in this way in heavy weather conditions, without sustaining severe shock loadings to both vessel and crew. At the other extreme, full 'displacement' type of hulls could be very good in heavy weather conditions, but had practical limits on powering requirements and speeds'. The RNLI needed vessels that could proceed as fast as possible in the range of weather conditions her crews encountered.

Vision!
David Stogdon, like so many of his fellow British designers, could not gain the backing and support to develop his ideas to fruition, the frustrations of the situation and his vision to see a water jet powered lifeboat in this country remained. The Dutch, however, showed great interest in developing his ideas and W. de Vries Lentsch (de Rijp) adopted and developed this water jet powered lifeboat design to produce the Valentijn 2000 class lifeboat, many such water jet powered boats now operate at their stations in Holland. What David wanted to see in this country was a lifeboat that was fast, had excellent manoeuvrability, was able to save young people at sea, when seconds counted, protected its crew from the severe conditions, whilst offering the best possible technical innovations that would serve them well for many future years. At Caister, we consider his vison has finally been realised in bringing the Valentjn 2000 Lifeboat to Caister, the only independent volunteer lifeboat station to operate a full offshore service 365 days a year in Britain.

Continuous development.
Through continuous development the design of the Valentijn 2000 water jet powered lifeboat has been refined, by observing working experience, in partnership with the KNRM - the Dutch national lifeboat institution. The construction of the new Caister lifeboat took place at the Habbeké Shipyard in Volendam the Netherlands, during the period of late 2003 to mid 2004, under the mangement of Arie de Waart, the boat builder. Arie has a continuous order book for this design and has already constructed many Valentjn 2000 lifeboats for the KNRM.

Initial hull construction

December 2003

The picture left shows an early stage of construction the aluminium components of the hull are immensley strong and rigid when put together in this way whilst remaining light in weight. Computer integrated manufacture ensures that individual component parts are precisley cut from sheet material before being welded, whilst located in jigs, to ensure uniformaty and adherence to the plan of construction. A skilled team of engineers operate at Habbeké, and we at Caister have every confidence that this is a job well done.