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  • ombugge
    commented on 's reply
    This was an equipment test and re-certification exercise, not a normal drill, or a normal lifeboat for that matter.
    Drills normally doesn't involve actually launching the lifeboats, or inflating the liferafts, only to muster and prepare the equipment.
    But I believe the common practice now is to minimize the number of persons on board while lowering and recovering to minimize risk.

  • PoloUK
    replied
    Fascinating posts Ombugge - so many combinations of scenarios to plan for and test.

    Leave a comment:


  • pilotdane
    commented on 's reply
    Is it now common to practice or test the lifeboats without people on board? I recall some fatal accidents when practicing life boat drills and wonder if they are minimizing the time people spend riding up and down in the boats.

  • ombugge
    replied
    Found it!!
    This is the portable diving spread on the DLB "Aziz" as seen on 14. June, 2011:




    The Hyperbaric Evacuation Unit (HEU):


    Instructions to anybody that recover the HEU:


    It even have Towing Bridle and Lifting Slings installed to aid in recovery:

    The diving bell and gantry at center.

    Here is a even simpler HEU installed on the Allied Conquest:

    Leave a comment:


  • ombugge
    commented on 's reply
    They are standard equipment on DSVs, where the de-compression chamber(s) are permanent and built-in.
    In case of portable diving spreads, portable Hyperbaric Evacuation Units (HEU) are used. These are self-buoyant and can be launched if the vessel they are installed on has to be evacuated. (Or will float up, if the vessel sinks)
    I think I have shown picture of a HEU somewhere on CVF earlier, but cannot remember where. (Will post, if found)

    The problem with all such system is that, in multiple chamber systems, divers may be in saturation at different pressure while the HEU is a single chamber. Going from a chamber at high pressure into one at lower pressure can result in the divers getting "the bends", or in worst case, collapsed lungs.

    How is this problem solved? All chambers are brought to the highest pressure, as is the HEU. The hatches between the chambers, the TUP and the HEU can now be opened and all the divers can move to the HEU. Decompression schedule will be based on the requirement of the/those diver(s) that has been in saturation the deepest, or longest.

    Accidents where divers have been in saturation and gone down with the sinking barge/ship has happened, the latest one as late as in 2011 off Iran: http://www.dnaindia.com/india/report...-coast-1602719

    The sinking of DB 29 in a typhoon off China in 1991 is maybe better known. 4 divers were decompressing in the chamber on deck when the barge capsized and sunk. No evacuation system was available and they went down to 220 ft. WD with the barge. All attempts to get them out failed: http://articles.latimes.com/1991-08-...09_1_hong-kong

    PS> I was Marine Adviser on board DB 29 a few months earlier, while she was laying pipe off Sarawak, East Malaysia.

  • Tommi
    replied
    Many thanks for the detailed report. I always get the feeling of being so unique close to the operations on board when watching your pictures and reading the informative texts. I didn't know that there are specialized life boats for divers, interesting.

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  • janihudi
    replied
    thank you,a very detailed report

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  • ombugge
    replied
    Last to leave close the hatch:


    Back in place. Gently being lowered onto the escape shute lock:


    ​End of test and end of report from DSV Skandi Singapore

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  • ombugge
    replied
    Returning to re-connect hooks:

    A little help from the FRC comes in handy.

    Hooked up and raised slightly:


    The Coxswain appearing from the hatch:


    Getting onto the FRC:




    Leave a comment:


  • ombugge
    replied
    Full ahead:


    The FRC following for safety:


    Turning to stay within Shipyard's jurisdiction:


    "Heavy seas":

    Created by the boat and FRC.

    A bit low on the bow due to position of water weight inside:


    Testing the sprinkler system:


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  • ombugge
    replied
    Next test involve releasing the falls while the boat is just above water. (On-load release test).
    The boat was lowered into the water without crew on board. The crew boarded form the FRC:


    Entering through the top hatch:


    The hatches secured. The boat is lifted just above water:


    The hooks are released from inside the boat:


    Moving away from the ships side:


    Leave a comment:


  • ombugge
    replied
    The Hyperbaric Lifeboat test may be interesting for some to watch. This particular boat has capacity for 18 divers and 4 crew.
    First phase was to test the davit launching system. This was done without people on board, but with water bags to simulate the weight of divers and crew

    The boat being lowered:


    No need to launch for this test:


    Recovered:


    End of weight test.
    Last edited by ombugge; June 29th, 2014, 08:22.

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  • ombugge
    replied
    The umbilical winch:


    For safety, the bell is launched and recovered by a 3-wire system, each with it's own winch:


    The wires are heave compensated for lanunch and recovery in fairly rough weather:


    The winches are controlled from this panel in the Dive Control Room:


    Dive Control Panel:


    View of the bell in stowed position through the window in the DCR:

    Leave a comment:


  • ombugge
    replied
    There is a built-in 18-man Saturation System with 3 chambers + TUP and Hyperbaric Lifeboat. (Sorry, no pictures of the chambers available)
    ​The Diving Bell is very large and sophisticated, capable of holding 3 divers and diving to 350 m. water depth.
    Here is seen the upper part of the bell:


    And here the rest:


    The entire bell, weighting some 23 m.t., including the launch frame:


    The launching frame sitting over the moon pool, ready to receive the bell:


    The connection is controlled from the DCR, but can also be controlled manually from this panel:
    But can also be controlled manually from this panel:


    Leave a comment:


  • ombugge
    replied
    Although the Skandi Singapore is primarily a Dive Support Vessel, she carries permanently installed two work class ROVs.
    Here is the one on Stbd. side as seen through the open ROV Hangar door:


    The other is permanently installed in the hangar on Port side, with LARS for easy launch and recovery:


    Aside from remote control from the ROV Control Room, the LARS can also be operated manually from this panel in the hangar:


    Leave a comment:

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