Manor Marine has been entrusted with the task of constructing and completely fitting out this large batch of pusher tugs, the first project they have undertaken for British Waterways. The barges are under construction elsewhere.

In the words of Mr John Tye, the company's operations director, 'Whilst these are the smallest vessels that Manor Marine has built to date, they are quite complex and compact, which makes for a challenging fit out.

The delivery times for the series of 23 vessels are very tight but this schedule has been met by a combination of the skills and work ethic of our labour force and the professional, 'can do' attitude of the British Waterways staff.

'Everybody concerned could not be anything but pleased with the outcome. Turnkey projects of this type can only be achieved on time, on budget and to standard if all parties involved are singing off the same hymn sheet and I would like to personally thank all the people involved in this project. We take great pride in the fact that turnkey projects are completed using our totally in-house labour force, a rarity in this day and age. The company carries a workforce of 66 people on the shop floor at present. The vast majority are time-served to the marine industry and have been with the company for many years. Manor Marine has always been a proactive company and as such has a view to the future and currently employs six apprentices at various stages of training.'

Manor Marine has been building vessels for a decade and specialise in steel or aluminium workboats under 24m. Previous work includes several vessels for the UK and Ireland and contracts for Russia, Greece and Nigeria. At present, vessel construction accounts for approximately 40% of the company's business, the remainder being made up of vessel refits and repairs. A loyal customer base includes the MoD, HM Revenue & Customs, SercoDenholm, Fisheries Protection, RNLI, Condor Marine Services, Brittany and High Speed Ferries.

The vessels currently under construction are the result of two years of development carried out by a working group of BW operatives, managers and engineers. Among the factors considered, were the need to meet current and foreseeable environmental, safety and operational standards. These include Maritime & Coastguard Agency rules and EU legislation likely to call for higher standards for working craft on inland waterways from 2008. Early indications are that many craft in the existing fleet will not comply with these new standards.

Prototypes for the tugs, barges and other components in the new modular system have been extensively trialled by BW in the West Midlands and elsewhere.

The tug design that emerged from that study was designed to meet the following key requirements in order to overcome the deficiencies present in the existing craft and to enable new and innovative methods of operation. A modern propulsion system with a 39hp diesel engine with low noise & emission characteristics and a hydraulic drive was specified to meet all applicable environmental standards.

The vessel's dimensions must enable the tug to turn within the width of a canal and push the hopper barges from either end, alleviating the problem of having to turn around using 'winding holes'. To aid mobilisation all craft must be of a common gauge and able to work anywhere on the waterways network. A new latching system allowing tugs and narrow hoppers to connect by remote control will be incorporated and must be compatible with future wider craft.

The tugs have separate washing and toilet facilities for the crew, with hot and cold water for hand washing. Also included is an onboard flushable toilet with a waste water and sewage storage tank. An enclosed cabin must be capable of carrying three people and incorporates an elevating mechanism to enable the skipper to see over high loads. Winches are provided for connection to older hoppers without a latching system.

The narrow beam tug was designed around the BW specification by Keel Marine Ltd of Alton in Hampshire based on previous designs, and taking care to incorporate the features previously mentioned along with modern production methods and materials.

Hull construction and the entire fitting out process is being carried out, undercover, in Manor Marine's Portland workshops on a production line basis. The fully developed, double chine, steel hull has a length of 6.00m, beam of 2.07m, a depth of 2.57m, draft of 0.73m and the finished craft weighs 4.8 tons fully loaded (ready for work).

Steel for the hull components was 'Plasma' cut using an in-house computer controlled CAD-CAM system. The result has been a very accurate assembly and straightforward welding process. All of the steel plate used in construction was supplied by Corus Steel in a grit blasted and primed condition and the finished vessels painted with two-part epoxy paint systems by International Paints.

The hull incorporates five watertight bulkheads separating the fore-peak, wheelhouse section, toilet compartment, engineroom and steering compartment. At deck level the hull is almost rectangular in plan view, has a counter stern and four 'push-knees' in the bow. The afterdeck and engine access hatch is completely flush and the only steel structure above the main deck is the toilet compartment, engine room vents and a low coaming around the wheelhouse aperture. Provision is made for lifting the craft by crane, with four neatly configured lifting eyes partially concealed at the deck edge (two forward and two aft). Mooring bits are fitted fore and aft, and there is a protective handrail above the transom.

To enhance efficiency in operation a hydraulic latching device is fitted to each vessel to enable a rapid connection to be made to the barges due to come into use at much the same time. The latch comprises a single 'T' shaped plunger mounted horizontally in the bow between the centre push-knees, on a hydraulic cylinder, with a secondary hydraulic mechanism allowing it to be turned through 900. On approaching a barge, the latch is turned to enable it to be engaged in a vertical slot in the bow or stern of the barge.

Once in position the latch is turned through 900 to the fully engaged position and the barge is drawn tightly into contact with the push-knees. Hydraulic power for the mechanism, which is operated from the wheelhouse, is supplied by an electrically driven hydraulic power-pack. To enable existing barges without a latching device to be handled, a pair of hand operated push/tow winches are mounted on the push-knees, each accommodating a steel wire rope.

Each tug is powered by a Beta Marine Green Line, BETA 39 BD1703 (fully marinised Kubota) three cylinder diesel engine developing 39bhp at 2,800 rev/min, chosen for its low exhaust emissions. The engine is keel cooled and drives a four blade, manganese bronze propeller of 457mm diameter via a hydraulic drive incorporating a 3:1 reduction. Mounted transversely, the engine drives the main propulsion fixed displacement hydraulic pump, one Iskra A127 70amp alternator, one 110 volt AC alternator/ generator and is fitted with a calorifier for vessel heating.

A water cooled exhaust manifold is fitted along with a dry exhaust system and 'hospital' standard Halyard silencer. The latter, in conjunction with a well insulated machinery space, gives the vessels a very low noise signature underway and while moored.

BW has specified that the engine must be capable of being changed within 2 hours to prevent unproductive downtime.

A minimum of 230 litres of diesel fuel is accommodated in a stainless steel tank located beneath the wheelhouse.

The hydraulic drive to the propeller is supplied by Hercules Hydraulics and comprises a very short conventional shaft and bearing housing, forming a demountable 'pod' with a direct coupling to the hydraulic motor, thus eliminating the need for a conventional stern tube and shaft assembly. A weed clearance trunk and hatch is provided above the propeller accessible from the deck. The tugs are steered by a conventional manual hydraulic system by Wills Ridley operating a single plate rudder.

A fixed water mist fire protection system by Elite Fire Systems Ltd is installed to enable safe working inside tunnels and other confined spaces.

The wheelhouse is capable of carrying a skipper and two passengers and has an elevating mechanism to allow the entire unit to be raised by some 500mm to improve visibility whilst working with craft having a high freeboard. With the wheelhouse in the lowered position the vessels have an air draft of 1.87m. Manufactured by Composite Mouldings Ltd, the wheelhouse shell is formed in Fibre Reinforced Plastics (FRP) with a structural foam core. Two sliding doors give access and a sealing arrangement is fitted at the hull/wheelhouse intersection.

The wheelhouse is elevated by a 'scissor jack' mechanism located in the compartment below and powered by a single hydraulic ram. Hydraulic power for . .

. . lifting the wheelhouse is supplied by the same electrohydraulic power pack as the latching mechanism, again supplied by Hercules. The latching mechanism and scissor lift assembly for the wheelhouse were both engineered by Shepcote Engineering.

All of the engine, propulsion, latching, elevating and ancillary controls are located in the wheelhouse. A helmsman's chair is provided for the skipper and all of the controls fall easily to hand. Warm air heating is provided and the structure incorporates a high level of thermal and acoustic insulation.

Anti-vandal window guards, formed from polypropylene, are proved for each window and when not in use are carried in a neat stowage arrangement behind the superstructure.

With the introduction of this new fleet of tugs and barges BW aims to simplify servicing and repair. Critical components such as engine and hydraulic pack will be capable of replacement on site and standardised spares and components can be held in stock or easily procured from carefully chosen suppliers.

The tugs will be regularly maintained to meet BW standards. A facility for remote monitoring the tug's systems, and location via a data link by a SCADA system is being developed for the entire fleet.

The overall configuration of the new fleet has been designed to change dramatically the ratio of powered to non-powered craft, typically one tug to three or four hopper barges, thus reducing machinery maintenance considerably.

Manor Marine commenced production of the first batch of 23 tugs in the Autumn of 2005. At the time MJ visited the company, 10 vessels had been completed, with the first deliveries to BW imminent.

The production line is in full operation and one tug per week will be completed until the contract is fulfilled.

Included in the overall project are innovative designs for modular 'workshop pods' and 'accommodation pods' capable of being loaded onto barges.

Workshop pods allow for safe storage of equipment and offer a dry working environment, whilst accommodation pods provide a rest area, cooking and sanitary facilities including flush toilets and hot and cold running water. The pods can either be transported to site by barge or, where possible, more efficiently and quickly by road on the back of 7.5 ton lorries. The barge design improves operative access and allows for flexible working as the barges can host a combination of pods, materials, excavators, cherry pickers or lifting equipment.

As a direct result of British Waterway's workboat fleet replacement programme, around 80 redundant workboats owned by BW were due to be sold by auction in an online sale.

Closing on 27th April 2006, the auction included 20 narrow workboats, 14 tugs, five grab dredgers, four pilot launches, three narrow boats, a weed cutter, a number of hoppers and other miscellaneous vessels.