WITH THE TIME APPROACHING when the RNLI's 46ft 9in and 47ft Watson class housed lifeboats will reach the end of their station lives, preparations have been going ahead over the past few years for their replacement by a new fast slipway boat. The requirement approved by the Committee of Management for this new boat was that, while retaining those characteristics which make possible housing ashore and rescue work in shoal waters —shallow draught, a long straight keel and protected propellers—she should have the added advantage of higher speeds than the boats she would supersede. In effect, a way had to be found of reconciling in one boat what had previously been regarded as two conflicting design features. Up till now it has only been the afloat lifeboats which have been able to reach speeds in the regions of 15 to 18 knots; the traditional slipway boats have been limited by their very nature to 8 to 9 knots.

Further requirements for the new boat were that she should have a selfrighting capability and that her dimensions and weight should be such that she would fit into existing boathouses and could be launched from existing slipways.

Here was a challenging project calling for an entirely new line of thought in small boat design, and in 1977 a steering group was formed under the chairmanship of Mr P. Denham Christie, a vice-president of the RNLI, to undertake the necessary development work. A start was made possible because, in fact, some of the necessary fundamental research was already being done by the National Maritime Institute as part of its basic research programme and the Institute very kindly undertook to provide the RNLI with a lines plan for a fast slipway lifeboat with propeller tunnels.

The next stage was an exhaustive programme of model testing. First there were tank tests at the National Maritime Institute to establish resistance, flow and powering data; then, with the co-operation of the British Hovercraft Company, trials of a radiocontrolled model were run at sea to obtain information about the proposed hull's manoeuvering, sea keeping and course keeping capabilities.

Progressive tests and development produced results which were sufficiently encouraging to allow detail drawing for the design by the Institution's staff to begin last year, and the work has now reached the point where building full size can start. Interested yards have been invited to submit tenders so that a decision on building the new fast slipway lifeboat can be made by the Committee of Management.

From the work so far done it would appear that this new design will make possible an increase of speed in a slipway lifeboat from the traditional 9 knots maximum to something over 15 knots. So, a breakthrough has been made of great importance, not only to the RNLI's future fleet but also to lifeboat services in other parts of theworld and possibly to commercial boats.

Because of this more general application and because of the new ground broken by this work and its safety aspects, the Government's Ship and Marine Technology Requirements Board (SMTRB) has taken great interest in the project and has expressed its willingness to give practical help. A design programme of this nature, entailing the building of prototypes for the intensive trails to which any new class of lifeboat must be subjected before boats can be sent to station, places a very heavy financial burden on the RNLI over and above its normal commitments. So, as there is mutual interest, it was decided that the work should be regarded as a joint project between the RNLI and the SMTRB from which both would benefit.

RNLI Trading Ltd and the SMTRB have therefore entered into an Agreement under which the SMTRB will contribute to the cost of the design and development of the fast slipway lifeboat. Two prototypes will be built which will be the property of the RNLI, but the industrial property rights for the design will belong to the SMTRB, to whom royalties will be paid for any boats built other than lifeboats for the RNLI or overseas lifeboat societies; one important provision of the Agreement is that overseas lifeboat societies will only be absolved from paying a royalty if the lifeboat is built in a British yard.

Much good will has been shown to the Institution by the Ship and Marine Technology Requirements Board in the drawing up of this Agreement which, as we approach the twenty-first century, will help the lifeboat service to keep pace with the future and which it is hoped will bring revenue to the Government and welcome overseas orders to British boatbuilders..