Glassboat Litus Izleti Excursions

Our catamaran glass boat LITUS was built in 2002, in Pula, according to the order of a small Croatian company LIT Malinska, dealing with the transport of passengers. The idea was to give the opportunity of enjoying the underwater world to all those people who cannot put on their diving suits and dive into the blue sea. Moreover, our intention was also to show them the beauty of Croatian coast and its islands. Thus, the catamaran glass boat LITUS, which is 17 meters long and 6 meters wide and has the capacity of transporting 110 passengers, has 12 windows at the bottom - about 1,5 meters below the surface of the sea. This is the reason that we proudly call our ship GLASSBOAT. On the ship, it is possible to spend time in a closed lounge, equipped with the tables and 40 seats, or at the ship's sunny decks. Inside the lounge there are the bar and the toilet facilities. The ship is registered to carry 110 passengers, has all the licenses and certificates issued by Croatian Register of Shipping. The ship is propelled by 2 engines, with the power of 221 kW each.

The history

The ship AQ 165 m/b LITUS, made according to the order by LIT company from Malinska, from island Krk, has been designed and built as a two engine vessel of a catamaran type, with the purpose of sightseeing under the surface of the sea and transporting 110 passengers.

Project was made by Boat's Consulting, a company from Rijeka, the technical preparation division of the 'Tehnomont' shipyard was in charge of manufacture documentation and the process of building the ship was supervised by HRB.

Main characteristics of catamaran LITUS
	Overall legnth..........................................................	17.40 m
	Legnth KVL..............................................................	15.50m
	Width.........................................................................	6.20 m
	Height below the upper deck.............................................	2.62 m
	Constructive gauge/draught................................................	1.70 m
	Displacement.....................................................................................	45 t
	Speed...............................................................	13 uzla
The hull is built in welded construction, with the longitudinal building system. The thickness of the shell plating, of the bottom, of the edge, of the deck, and of the whole superstructure is 4 mm. The transverse webbing is made of L profiles 60 x 30 x 5 which are strengthened by TZ 120 x 5/40 x 6 transverse ribs. At the left and the right shell plating of the bottom, in both hulls, between the framework ribs there are acrylic glass plates (700 x 1260 mm) for sightseeing below the sea surface. Sealing and the watertightness between the frames and the glass are done by SIKAFLEX 291 material. In each hull there are three watertight bulkheads, dividing the hulls into the four watertight spaces: the bow collision space, the crew cabins, the space for viewing the bottom of the sea, the engine. All these spaces can be entered by ladders or stairs.

The ship propulsion system consists from two independent and separate propulsion units of IVECO AIFO 8361 SRM 40 type, each situated in one hull, with the nominal power of 220 kW at 2400 min"1. Transferring of power to the spindles of ship's screws is provided by the ZF IRM 301 C type reductors, i = 2, 693. The basis of the main engines and gearboxes (reducers) is provided by the solid rendered plates. The screw and stuffing boxes ('šupernicas') of this vessel were delivered by a manufacturer from The Netherlands, and the remaining elements of the axial lines (conductors) were made in the 'Tehnomont' shipyard in Pula, Croatia. The bearings of the stern tubes are made from polytetrafluoroethylene (‘metaflon’) that does not need additional cooling.

In the ship's superstructure are the main deck, the steering room, the passenger lounge, a bar, the fire emergency CO2 space and two toilets.

The rudder/navigation room is equipped by a bench board for steering the vessel, controlling and operating the main engines, with the electricity cables cabinet, navigation and signalization devices.

The ship has two tanks of drinking water, with the overall capacity of 1500 1 and four fuel tanks with the capacity of 2820 1. The fire emergency CO2 system is provided for the engine rooms, and the rest of the ship is equipped with fire extinguishers. Each main engine has its own independent system of cooling with the seawater by the heat exchangers. The general utility pump (bilge + fire extinguisher) enables also the auxiliary cooling of the main engines. For the engine room, the ventilation is done by air throttle ventilators with overall capacity 1440 m3/ h, controlled from the rudder/navigation room. The basic electrical power system of the vessel is a two- duct system of 24 V single polarity. The following sources of electricity are provided: accumulator battery for starting the main engines, the 24 Vi 180 Ah general purpose accumulator batteries, the emergency accumulator batteries 24 V and 180 Ah, with alternators connected to the main engines. The navigation and signalization equipment consists of the following: magnet compass, VHF device, ship sirens and navigation lights. Steering is done manually, from the steering room - by the hydraulic pump and separated hydraulic cylinders situated in each hull. The cylinders which are connected by the mechanical connection with the hanging rudders are of the machine type.

The ship is painted by the Hempels Marine Paint system. In order to achieve the perfect form without bumps, at the coating the epoxy filler kit was applied before painting. All the paints were applied according to the clear specifications under the supervision of the painting inspector. At the underwater part of the vessel's hull, the proper number of zinc protectors is installed for passive cathode protection

Having in mind that, when the shipbuilding business is mentioned in the public, the attention is mostly given to the part of shipbuilding business concerning the big shipyards and building big ships, and that the small shipbuilding business is mentioned rarely, maybe this is the right occasion for mentioning a few comparisons between small and big shipbuilding business.

One of the problems, when the building of the small vessels is concerned, is that there are small spaces which are hardly accessible or even inaccessible to welders. Thus, it is necessary to give the lot of attention to the construction, in order to avoid the manufacture problems.

The tin plates are a lot thinner, and thus the deformation problems are more expressed, compared with the building of the big vessels.

The possibility of automatization and robotization is smaller or none, but that is an advantage, because the small shipbuilding business has no problems with technologically more advanced competitors, such as the building of the big ships has.

In small shipbuilding business the productivity is less expressed (deposited materials) in welding, and the more attention has to be given to the high quality of preparations and welding.

The small shipbuilding business can find its place even in Croatian market, especially in tourism, and the building of Litus vessel also proves that fact.