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opportunity. Launching, retrieving, supporting and maintaining a vehicle 

 up to 192t weight calls for a surface platform of considerable magnitude, 

 a highly-skilled crew and an extensive inventory of specialized equipment. 

 For such reasons many of the pipe-trenching and cable-burial vehicles operate 

 from dedicated support platforms. An appreciation for the components and 

 support ship requirements of pipe trenching vehicles can be gained by reviewing 

 the dedicated support ships of two systems, PBM and TM III. 



PBM - Shipboard _ Components : Control cabin, hydraulic power pack, high pressure 

 water pumps, air compressors, umbilical winch and cable, electric power 

 generator, handling system, workshop van. 



Support Ship Requirements : For shallow water (less than 50m depth) in good 

 weather: a small supply vessel equipped with a 20t A-frame, an 8-point 

 mooring system, open deck space to accommodate shipboard components, shallow 

 diving equipment and accommodations for a crew of 12. For deep water : a larger 

 craft v/ith a 50t A-frame, one deep diving unit and accommodations for a crew of 25. 



TM III - A specially designed and dedicated pulling/jetting barge, L.M. BALDER, 

 is used to support this vehicle, its characteristics are as follows: 



LOA: 110m (361 ft). Beam: 30m (98 ft). Draft: 7.7m (25.2 ft) 



DWT: 15,000 



Anchorage System: Four double-drum Skaggit winches with 750m (2,460 ft) 



of 50mm (2 in.) wire rope and eight 7.5t anchors 

 Storm Anchor: One electrically driven windless with chain and 5t anchor 

 Accommodations: 80 berthing and full messing 



Craneage: One crawler crane with 25m (82 ft) boom, maximum lift 

 of 136t (150 tons) . One crawler crane (deck traveling) of 54t 

 (60 tons) maximum lift 

 Navigational Equipment: Radar, Hi-Fix, Trisponder, Tellurometer 



These two pipe trenching support craft reflect only the requirements of a 

 specific system, other pipe trenching vehicle support requirements fall some- 

 where in between these. Where most pipe trenching vehicles rely on a moored 

 support platform, the KVAENER MYREN system calls for a dynamic positioning 

 system to hold the support ship on station, other specific support requirements 

 are contained in Appendix D. 



Support facilities for Vicker's cable burial vehicle, SEACAT, are unique, in 

 that either a diving system or a manned submersible (depending on depth of 

 operation) must be available to control and monitor the vehicle in situ. 

 (SEACAT, therefore, is not truly a remotely controlled vehicle since it relies 

 upon manned intervention for operation.) Details of the support ship requirements 

 for SEACAT are not available. Hov;ever, manned submersible support vessels 

 of the Vickers fleet (VICKERS VOYAGER, VICKERS VANGUARD, VICKERS VIKING, etc.) 

 are equipped to handle SEACAT and its attendant support equipment. 



Surface support requirements for bulldozers are minimal since the vehicle 

 works in one location and, generally, not far from the shoreline. In one 

 instance - the shallow version of JH 160- the operator can control the vehicle 

 from the shoreline or a pier by merely observing the orientation of its mast. 

 The following components and requirements apply to the deep water version of 

 the JH 160 bulldozer. Appendix D presents the support ship requirements and 

 surface components of the JH 160 system. 



