Test 2025 variante 2
Which of the following position references is based upon an absolute position reference principle?
DGNSS
When a vessel arrives on a new contract for a Client which of the following set of tests shall be appropriate?
Field Mobilisation Checklist
Laser systems that do not have a target have advantages and disadvantages. Which of the following disadvantage should be considered in PRS selection?
Low range compared to other relative systems.
When might it be a good idea to deselect a wind sensor in a specific location during operations?
During Heliops
Where is the best position for an IJS?
In a location in close proximity to the main DP control system so it can be quickly engaged if the need arises.
Which of the following is a physical measure to prevent a blackout?
Phase back of large running consumers.
What should be the effect of a failure of a single tension sensing device?
Positioning should remain stable with no adverse thrust reactions
What is a DP system FMEA? (Ref: IMO MSC 1580)
A study that identifies single failure modes and assesses them against a design worst case failure to ensure the vessel can maintain and heading position under those single fault conditions.
What sub systems form a vessel dynamic positioning system? (Ref: IMCA M103)
A Power system; thruster system; and DP Control System.
In IMO MSC 1580 how are DP equipment classes categorized? (Ref: IMO MSC 1580)
Equipment Class 1; Equipment Class 2; Equipment Class 3
What is the definition of equipment class 1 vessels? (Ref: IMO MSC 1580)
A loss of position or heading may occur in the event of a single fault.
What is the definition of equipment class 3 vessels? (Ref: IMO MSC 1580)
A loss of position or heading will NOT occur in the event of a single fault in any active or static component or system or loss of compartment due to flooding or fire.
How is single failure criteria for DP equipment class 2 vessels defined? (Ref: IMO MSC 1580)
Redundancy of all active components.
What does IMO MSC 1580 require in a DP annual survey? (Ref: IMO MSC 1580)
An annual survey that confirms maintenance of DP systems, the systems functionality and the ability to keep station after single failures associated with the equipment class witnessed by officers of the flag state or nominated surveyors or organisations.
What is a power management system? (Ref: IMO MSC 1580)
A system that ensures continuity of electrical supply under all operating conditions.
What DP capability plots should be available on-board? (Ref: IMO MSC 1580)
For the fully intact thrust and Worst Case Failure (WCF) thrust scenarios.
Upon the loss of all position references what will the DP system do? (Ref: NI)
The DP System will maintain a dead reckoning position, giving time to consider options.
What is the DPOs correct response when the ASOG indicates a GREEN condition "Normal operations - all systems fully functional and operating within acceptable performance limits"? (Ref: IMCA M103 3.5)
Commence and continue operations as planned.
What is the DPOs correct response when the ASOG indicates a YELLOW condition "Reduced status Pre-defined performance limits reached, component or system failure resulting in loss of redundancy"? (Ref: IMCA M103)
Commence preparations to safely terminate operations.
What is the DPO's correct response when the ASOG indicates a RED condition "emergency status pre-defined operational or performance limits exceeded, component or system failure resulting in loss of control or position, internal or external emergency situation affecting the vessel"? (Ref: IMCA M103)
Abandon operations. Take immediate action, i.e. initiate emergency disconnect sequence (EDS) to ensure the safety of people, the environment, the operation and the vessel
What is the DPO's correct response when the Critical Activity Mode (CAM) is BLUE "Advisory status - where any of the GREEN conditions are not met"? (Ref: IMCA M103)
Conduct risk assessment to determine whether to continue, change position or cease operations
How long should the initial stabilization period be when setting up on location? (Ref: IMCA M103)
The initial stabilisation period should be at least 30 minutes.
Within the DP Industry how is a loss of position and/or heading defined? (Ref: IMO MSC 1580)
The vessel's position and/or heading is outside the limits set for carrying out the DP activity in progress.
How is redundancy defined? (Ref: IMO MSC 1580)
The ability of a component or system to maintain or restore its function when a single failure has concurred.
The consequence analysis verifies the position keeping ability of the vessel after what event? (Ref: IMO MSC 1580)
A Worst Case Failure (WCF) situation.
When should redundant components be available? (Ref: IMO MSC 1580)
Redundant systems should be immediately available without needing manual intervention.
Equipment class 1 vessels require which of the following DP Control System arrangements? (Ref: IMO MSC 1580)
The DP Control System requires at least one DP Controller but no redundancy (ie two DP controllers) is required.
What three decision support tools promote proper planning and control for successful DP Operations? (Ref: IMCA M103)
Activity Specific Operating Guidance (ASOG), Critical Activity Mode (CAM), Task Appropriate Mode (TAM).
When should field arrival trials be conducted? (Ref: IMCA M103)
Field arrival trials should be carried out on arrival at the field and conducted outside the 500 metre safety zone. The checks should be repeated when the vessel returns to the field after an absence of more than 24 hours.
What equipment should be checked during DP field arrival trials? (Ref: IMCA M103)
Thrusters, power generation, auto DP, independent joystick (US) and manual controls.
Within what parameters should a fully operational DP system be able to reliably keep a vessel in position? (Ref: IMCA M103)
As defined by the rated environment for the DP vessel defined by the capability plots.
With respect to the environment and available thrust, when should consideration be given to suspending operations?
When the environmental conditions (e.g. wind, wave, current etc) are such that the DP vessel will no longer be able to keep position in the event of its worst case failure as stated in the DP FMEA.
Which of the following is a decision support tool for DP operations? (Ref: IMO MSC 1580)
Activity Specific Operating Guidelines (ASOG)
Who should be involved in testing and rehearsing emergency communications within the 500m zone? (Ref: IMCA M205)
Vessel crews and crews of nearby structures or vessels.
The vessel is operating on three DGNSS systems supported by different redundant supplies. Two GPS based and one GPS/GLONASS. Does this meet Equipment Class
2 PRS (position reference system) requirements? (Ref: IMCA DP SKB)
No. As DGNSS is a single reference, common mode failures exist, such as scintillation, sunspot activity and multipath issues.
Position reference systems (PRS) are comprised of which two systems? (Ref: MTS)
Absolute and relative.
Which of the following PRS groups are ALL RELATIVE references? (Ref: MTS)
Artemis; Laser; Radar.
An acoustic system is normally considered as an absolute reference system. Can it be considered a relative reference system under certain circumstances? (Ref: MTS)
Yes if the transponder / beacon is fixed to a non stationary object. Such as a spar / TLP / ROV etc.
In order for a DP system to function, what sensing systems are used by DP system manufacturers as inputs into the DP control system? (Ref: IMO MSC 1580)
Vessel heading, vessel motions and wind speed / direction.
While working alongside the installation, one of your thrusters fails to 100% pitch. Which of the following two words correctly replaces the blanks? _ _ safely
suspend operations while ensuring position is stable, notify all relevant parties of a — _ follow your escape plan and depart the 500m zone in a controlled
manner.
Deselect the thruster / yellow alert
You are the DPO on watch at the DP control station while answering a question to the client representative, you hear thrusters ramping up. When you turn to view the "Thruster "page (see diagram) on the DP system you see both bow tunnels are using 95%-100% thrust in opposite directions. Both thrusters have high level alert alarms. How do you know which thruster is the faulty thruster that should be shut down via e-stop?
You are conducting DP operations on a fully redundant DP-2 vessel (see diagram) and are fully compliant with CAM-ASOG when T2 (aft bow tunnel thruster) trips offline. The vessel crew initiates Yellow-Alert as per their ASOG, completes controlled disconnect procedures and exits the 500m zone for trouble-shooting and reactivation activities. Once outside the 500m zone it is determined that the vessel does not have the required spare components to reinstate T2 (Aft-Bow Tunnel Thruster). Can the vessel resume operations under CAM as a fully single fault tolerant vessel?
You are conducting DP operations on a fully redundant DP-2 vessel (See diagram) and are fully compliant with CAM-ASOG when DG 1 (Generator No. 1) trips offline.
The vessel crew initiates yellow-alert as per their ASOG, completes controlled disconnect procedures and exits 500m zone for trouble-shooting and reactivation activities. Once outside 500m zone it is determined that the vessel does not have required spare components to reinstate DG 1 (generator No.1). Can the vessel resume operations under CAM as a fully single fault tolerant vessel ?
Which of the following statements about the possible consequence of deselecting a drifting reference is false?
Deselecting a drifting reference is something that may be done at any time with no consequence on a modern DP system with multiple references online
What is HOS philosophy for PRS selection (vessel equipped with two relative (microwave & laser) and two absolute (DGNSS) PRS) and DP mode when going alongside a FPSO on a turret moor which will be weather-vaning?
Both relatives online, selected into DP System and on Auto-DP. DGNSS to be online and available but not selected into DP System
The vessel is alongside a drillship with all thrusters online, fully redundant in DP-2 Class with the following sensors online: 3 x Gyros, 3 x Wind sensors, 3 x VRS, 2 x DGNSS, 1 x Cyscan & 1 x radascan. The vessel is instructed to relocate 200m from the asset maintaining current configuration. The drillship notifies the vessel that it will be making a 35° heading change. Should any actions be taken prior to the drillship conducting the heading change as the vessel is already a safe distance from drillship?
With both absolute and relatives in use when the drillship makes a heading change there is a risk of divergence of sensors resulting in a drive-off scenario.
The vessel should deselect relative sensors and allow for stabilization prior to drillship conducting heading change
As per the diagram, you will be going alongside a FPSO on a turret moor for cargo transfer operations, port side to in a bow to bow configuration. During 100m validation and verification checks, due to FPSO movement being negligible, the decision is made to select both relatives and two DGNSS into system. After 30 minutes while monitoring sensor page or Pos-Plot page you note position references in diagram on right. What is the correct statement based on the position references?
As per the diagram, the vessel will be going alongside a FPSO on a turret moor port side to and bow to bow. If just using two relative sensors (CyScan and RadaScan) into the DP System, would the vessel follow the movements of the FPSO even when using Auto-DP mode?
The vessel is alongside a FPSO on a turret moor conducting operations at forward crane with targets (CyScan and RadaScan) mounted forward. Two DGNSS are available but not selected into the DP system. Cargo transfer is completed and the OIM informs you that they have two lifts left on the aft crane before releasing the vessel. Which answer describes correct course of action?
Move to 100m, bring both DGPS sensors online to calibrate them, then deselect both relative sensors. Call the OIM and instruct them to move both relative targets aft and into a position so that the aft crane will not block them. Once targets have been moved, bring them back online, calibrate, and deselect DGPS before moving into position under aft crane
You are conducting DP operations on a fully redundant DP-2 vessel (see diagram) and are fully compliant with CAM-ASOG when T3 (drop-down bow azimuth thruster) trips offline. The vessel crew initiates yellow-alert as per their ASOG, completes controlled disconnect procedures and exits 500m zone for trouble-shooting and reactivation activities. Once outside 500m zone it is determined that the vessel does not have required spare components to reinstate T3. Can the vessel resume operations under CAM as a fully single fault tolerant vessel?
The vessel is standing by inside the 500m zone and is instructed to come back alongside under the aft crane to complete the remaining few cargo transfer lifts. What is correct procedure or best practice ?
The vessel is to come to a complete stop at 100m and come to operational heading. Complete the 100m validation checklist. Bring relatives online and confirm no divergence of sensors. Complete 10 minute hold test before making apporaches via set-point moves
What should DPOs be cognizant of if the final working position of the vessel will be alongside a drillship which is providing a lee?
Upon entering the lee, there can be a sudden change in calculated current which could affect station keeping ability of the vessel
How does the CAM (Critical Activity Mode) support safe and predictable DP Operations onboard your vessel?
The CAM defines the most fault tolerant configuration of the DP system and equipment.
The vessel is positioned alongside a drillship conducting pumping operations when a consequence analysis alarm is received. What actions, if any, should be taken?
The DPO should recognize the fact that an intermittent consequence alarm is an indication that the vessel is outside of its post worst case failure DP capability and in yellow status per ASOG. The vessel should suspend operations and relocate at 100m from the facility / asset. If consequence analysis can be resolved by a heading change, the vessel is to conduct 100m verification checks and hold test and can re-approach work location per set-point moves as per ASOG. If consequence analysis alarm cannot be resolved vessel should relocate outside 500m zone
As per the diagram while conducting DP Operations with a floating facility you receive a "Median Test" alarm on RadaScan. Would there be any undesired consequences if you deselected RadaScan
What would be the correct procedure when approaching a drillship which is not fitted with CyScan prisms or RadaScan responders?
After completing the 100m validation, 100m checklist, and hold test, move via setpoints as per the ASOG to the work location, pass up the prism and transponder via the drillship's crane, and step out to create a 50m steel-to-steel separation. Once at 50m and confirmed targets have been properly mounted and won't be moved, ensure all sensors have a good grouping and no divergence before selecting relative sensors into the system. Once selected into the system, proceed to work location via set-points as per ASOG
What is the correct course of action if you are conducting operations alongside a facility/asset and detect divergence between position reference sensors?
Suspend operations and move to safe location => 100m before attempting to calibrate or deselect drifting sensor
As per the diagram, the vessel is alongside a FPSO on a turret moor and conducting DP operations with (1) Radascan and (1) CyScan selected and vessel in Auto-DP. If there are no sensor failures, alarms or sensor performance issues why are the two sensors not indicating the same position?
The vessel is on the east side of the platform unloading deck cargo when instructed to reposition on the west side. What should the vessel do prior to positioning at the west side of the platform prior to resuming operations?
The vessel should reposition at a minimum of 100m from the facility and conduct appropriate checks and set-up as indicated under 100m checks in the 500m checklist
What is the closest steel to steel separation allowed according to HOS policies?
10m