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Operational modes

QUEST Launch and Recovery

QUEST is generally operated in free flying (or "live boating") mode, which means there is a direct connection between the steel armoured umbilical cable, the vehicle and the winch. Thus, the vehicle has to be capable of pulling a certain part of the cable to gain spatial freedom when deployed. In order to achieve this capability, 10 - 12 float units are manually attached to the umbilical during deployment, reducing cable weight to become neutrally buoyant some 20 m behind the vehicle.

Deployment and recovery are both carried out in close cooperation between QUEST team members and ship's crew. In general, 2 pilots fly the vehicle, a deck supervisor advises pilots while the vehicle is at the surface, and the ship's crew handles the heavy load equipment such as ship's lifting winches and A-frame, and of course provides a precise vessel navigation. Typically, the vessel's aft deck will be closed to anybody not involved into the deployment/recovery procedures.

Launch and recovery requires increased working personnel from all parties, including scientists, ship's crew and ROV team. Thus, it is appreciated if launch and recovery procedures are planned at times where the majority of the required personnel are already on their feet. 08:00, 12:00, 16:00 and 20:00 have proven to be best for the usual watch cycles german vessels operate under.
Diving operations and turn-around times

12-hour diving operations on a routine daily schedule are performed during daytime, preferrably between 08:00 and 20:00. Prior to any dive, a 2 hour pre-dive check is carried out by the ROV team to ensure all systems are operating. After the dives, a 2 hour post-dive check is necessary to recover the vehicle entirely from its operational state.

During 12h operational mode, the turn around between dives is 12 hours, including recovery time for the QUEST crew. More time is needed if any adaptions for the next dive are planned, or if any technical issues occured and have to be solved. A shorter turn-around may be on exception be considered if previous dives were substantially shorter than 12 hours AND the turn around happens during daytime.

Continuous 24-hour diving operations can only be performed when applied for during cruise preparation prior to the coordinative meeting, since the QUEST crew has to be increased (see personnel requirements below) and a shift system has to be run during the major part of the expedition. This mode allows long dives, and a continuos dive/repair cycle in case technical issues do occur.

The minimum turn-around time during 24 hour operation is 6 hours, assuming there are no major setup changes or any technical issues.

Personnel Requirements

Depending on the operational mode of 12 hour or 24 hour diving, the QUEST team will consist of 8 or 9 crew members, respectively.
The following positions are defined during operation:
PositionQUEST Crew needed12h (2x6h shift)24h (6x4h shift)
In addition, the following scientific positions are to be filled during dive operation:
PositionScience Crew neededWorkspace
Sci. dive leader1Control van
Protocol writer1Control van
Navigator (GIS)1Lab
Observerany numberLab

Deck footprint and vessel interfacing

The complete QUEST system fits into 4 x 20' ISO Containers, a total of 45 t equipment including the containers. On the vessel's main workdeck, the following installations are necessary:
QUEST vehicleca. 3.5 x 2 mca. 3.5 tmain deck
Winchca. 4.5 x 2 mca. 15.5 tmain deck, 90° to ship axis
Control vanISO 20' twistlock rasterca. 8 tmain deck, close to vehicle
Workshop vanISO 20' twistlock rasterca. 6 tmain deck
ROV transport vanISO 20' twistlock rasterca. 2.5 tempty or storage space
Winch transport vanISO 20' twistlock rasterca. 2.5 tempty or storage space
LARSca. 1.5 m diam.ca. 1 tmounted in A-Frame
Electrical interconnection to the vessel is needed for power, data and video transmission. No hydraulic interfacing is used. Typically, the following connections will be installed (updated April 2012):
FunctionSpecificationCable and TerminatioinComment
ROV system power400VAC 50Hz, 250A switch4x95 mm2 to M12 ring terminalsmain propulsion power, max 180A
Winch power400VAC 50Hz, 250A switch4x95 mm2 to M12 ring terminalsmain winch power, max 150A
Control van power400VAC 50Hz, 63AStandard CEE (3P+N+PE) 5x63Astabilized, for computers, lights and AC, max 45A
Workshop van power400VAC 50Hz, 32AStandard CEE (3P+N+PE) 5x32Anon-stabilized, for lights, heater, tools, max 32A
Ethernet10/100/1000 MbitCAT 5, RJ45connect to ship's network
Video distributionspecial conversion, XGA 1280x1024 pixelCAT 5/7, RJ45 or SC MM Fibre, or network stream via IPtiled subsea video signal distributed to labs
HDTV distributionHD-SDI SMTP292MBNC, special HDTV coax cable1 single cable to Lab HDTV display (DVI-D)
USBL sync+5V/0V TTL-signalBNC / RJ45, CAT5Posidonia or equiv. USBL electrical Trigger signal
Telephone-RJ 11 or customTelephone to ship bridge, labs, cabins
Intercomcustomcustomopen science talk between van and lab