DP CPD

Class 2 DP is equipped with 2 bow tunnels and 2 azimuths on the stern. One azimuth thruster is out of service for maintenance. The effect on DP operations would be that. Operations requiring the vessel to be Class 2 would not be permitted. Operations requiring the vessel to be Class 1 would not be permitted even if the one remaining azimuth has sufficient thrust to counteract environmental conditions. Operations requiring the vessel to be Class 2 would be permitted because the vessel has a Class 2 certificate. No DP operations should conduct with the thruster out of service.

A Class 2 DP vessel is equipped with 2 electrically driven bow tunnel thrusters. During a DP operation, one of these thrusters fails to full force. The DPOs first action should be to. Activate the emergency stop for the failed thruster. Deselect the failed thruster from the DP Operator Station. Advise the Master of the problem. Inform the engine room and ask them to fix the problem.

A DP Class 1 vessel. is not able to maintain position automatically. Have at least two computers. Has the highest standard of system redundancy available. May lose position and/or heading of a single component in the DP system fails.

"A DP Class 2 or 3 vessel is fitted with four Position Reference Systems (PRS); 2 DGNSS, Taut Wire and Laser. In this instance, why should the DPO prefer to consider the 2 DGNSS as just one PRS? Q1 24". DGNSS systems are less reliable and accurate than surface systems. This is required by the IMO Equipment Class rules. Common-mode failures may occur to all DGNSS systems, whereby one event could result in a loss of all DGNSS position references. The DP Classification societies require this.

A DP mode whereby a vessel is automatically holding position relative to a surface installation or mobile subsea object that is moving is: Follow target/Follow sub./Follow ROV. Minimum power/Weathervane. Track follows. Auto DP/Auto position.

A DP system is divided into seven major hardware elements. Which element is the user interface for the DPO?. DP Operator Station. GMDSS. Environmental Reference Systems. Position Reference Systems.

A DP system is considered to have 'redundancy' when the vessel has: More than one Positioning Reference System. The ability to maintain position and heading subsequent to a single point failure. More than one DP Operator Station. More than one Gyro Compass.

A DP vessel is equipped with 2 tunnels thrusters forward, 2 tunnel thrusters aft, 2 main engine/propellers/rudders. During DP operations the Port main propeller fails to full ahead pitch which causes a drive off in the direction of a nearby platform. The DPOs first action should be to. Deselect the failed thruster from the DP Operator Station and inform the engineers. Inform the engine room and ask them to investigate the problem. Activate the emergency stop for the failed thruster only if full thruster redundancy is maintained. Activate the emergency stop for the failed thruster and inform the engineers.

A DP control system (Control Computers, Operator Station, etc.) is protected against a main power failure or fluctuations of the main power supply by: The UPS which filters the power./Being connected to on Uninterruptible Power Supply including battery back Up. Having a backup DP control system. Power management system. Automatic voltage regulator on the generator.

A DP system is divided into seven major hardware elements. Which element is the user interface for the DPO?. GMDSS. DP Operator Station. Environmental Reference Systems. Position Reference Systems.

A DP system using the 'preferred method of sensor allocation is fitted with two Gyro Compasses; both are selected into the DP system and one is chosen as the 'preferred" Gyro. The system alerts you that there is a "heading difference error' between the two Gyros. What would you do?. Immediately change the preferred Gyro. Call the Platform or Rig for assistance. Deselect both Gyros. Compare the two Gyros with the Magnetic Compass, before deciding whether to change the preferred Gyro.

A local Positioning Reference System is measuring from a local Reference Origin. Examples are: Artemis, Taut Wire, FMCW Radar and Laser. Artemis, DGNSS and Laser. DGNSS, Taut Wire and FMCW Radar. DGNSS, Artemis and FMCW.

A PSV is in the Follow Target Mode and is following a Semi-Submersible in Position and Heading. Which is the best combination of the PRS for the PSV. 2 DGNSS, ROV-with Transponder. DGNSS, Artemis, Radius. Radius, Fan Beam-with at the one Prism on the Semi Sub. Taut Wire. 2 DGNSS, 1 Fanbeam –with at the least two Prisms reflectors on the Semi Sub.

A thruster Bias mode can be selected: to avoid unnecessary fuel consumption. When Azimuth Thrusters continuously hunt for direction in low environmental conditions./To limit thruster azimuthing in light environmental condition. on a Tunel Thruster. In the Northern Hemisphere only.

About what point does a DP vessel rotate when changing heading?. The vessel's Centre of Gravity. A point mid-way between bow and stern. The vessel's Centre of Rotation. The location of the motion sensors on the vessel.

"According to IMO MSC/Circ. 654 of 1994, for what time period should an Uninterruptible Power Supply UPS battery system power the DP computer system following a mains supply failure?". A minimum of 15 minutes. A minimum of 30 seconds. A minimum of 30 minutes. The minimum time required for the emergency generator to switch in.

By what means do classification societies assess the demonstration of fault tolerance within DP systems?. The Failure Modes and Effect Analysis (FMEA). DP Operations Manual. Activity Specific Operating Guidance (ASOG). A HAZID / HAZOP study conducted as part of the vessel build process.

Differential correction for GNSS system may be transmitted as: HF. MF. Satellite signals. Any of these methods.

If a platform has just one Artemis antenna, how many vessels can be positioned using Artemis as a Position Reference Systems?. Two vessels provided that they have different frequencies. Five vessels. All vessels within a 5 km range. One vessel.

Dynamic Positioning can be defined as a system which: Controls a vessel's position and heading based on joystick inputs from a DP operator. Automatically controls a vessel's heading exclusively by means of active thrust. Automatically controls a vessel's position and heading exclusively by means of active thrust. Controls a vessel's position and heading based on manual inputs from individual thruster controls.

Excursions about a set point are expected when operating on DP. For vessel working to DP Class 2 requirements which of the following would you expect not to increase the excursions?. Loss of half the available thrusters. Position reference sensor variability. Incorrect control system tuning. A change in the environmental conditions.

Examples of Positioning Reference Systems (PRS) that can use multiple targets are: Laser and GNSS. Laser and DARPS. Laser and FMCW Radar. Laser and Taut Wire.

For DP Class 2 and 3 operations, at least three Position Reference Systems should be deployed and selected into the DP system. Why should they not all be based on the same principle. DPO is only trained on the type of Position Reference System. Because of the improved accuracy available from this configuration. So that if one PRS fails, the vessel remains fully operational. To protect against Common Mode Failure.

For DP Class 2 and 3 operations, at least three Position Reference Systems should be deployed and selected into the DP system. Why should they not all be of the same type?. So that if one PRS fails, the vessel remains fully operational. To protect against Common Mode Failure. Because of the improved accuracy available from this configuration.

For DP operations, how much settling time in Auto Position mode should normally be allowed before commencing work?. 15 minutes. 90 minutes. 60 minutes. 30 minutes.

How does a controllable pitch propeller work?. RPM constant, propeller blades change " angle of attack" on the hub and direction of rotation reversed to go astern. RPM varies form zero to 100 percent, propeller bldes fixed and direction of rotation reversed to go astern. RPM varies from zero to 100 percent, propeller blades fixed and direction of rotation constant. RPM constant, propeller blades change "angle of attack on the hub and direction of rotation constant.

How many Position Reference Systems should be available and online during a Class 2 operation, according to IMO Recommendations?. 1. 2. 3. 4.

How do you increase thrust with a Fixed Pitch Propeller?. By changing the "angle fo attack" of the propeller blades. By increasing the RPM. By changing the direction of rotation. All of the above.

If a position discrepancy among three or more Position Reference Systems is detected, the DP system will reject the drifting PRS as a result of the: Calibration test. Redundancy test. Median test. Consequence Analysis.

If a DP system component fails, the loss of position and/or heading can be prevented by: Higher speed computers. The provision of redundancy. Calibration tests. More reliable processors.

If the DP console on a Class 1 vessel has a total loss of power while the vessel is on Auto DP, the DPO can control the vessel's thrusters by switching to: Auto Track Mode. DP Autopilot Mode. Joystick Mode on the console. Independent Joystick control.

If a Thruster (which is not connected to a Shaft Generator/Alternator) fails to full force, the DPO should immediately: Call the Master. Activate the Emergency Stop for the failed thruster. Deselect the failed thruster from the DP Operator Station. Inform the engine room.

In a Hydroacoustic Position Reference (HPR) System, a Responder Beacon is a device which: Is Interrogated through water and replies through water. --- Interrogated through cable and replies via cable. Sends continuous acoustic pulses from the sea floor. ----Will send out a ping every 30 seconds. is interrogated by electrical signal through cable, replying through water. ----Receives a trigger signal via a cable and replies via water column. Is interrogated through water and replies via cable.----Can only receive and not transmit acoustic signal.

In fog conditions at a range of 100m which position reference system will you not be able to use?. GNSS. Laser. Artemis. FMCW Radar System.

in the Universal Transverse Mercator (UTM) system, how many Zones are there?. 24. 12. 60. 48.

Reception of GNSS satellite data is affected by which one of the following environmental factors. sun spot activity. rain. cloud. fog.

On a PSV alongside an installation a sudden high unexpected increase in DP current Residual Force is observed. What is the most probable reason?. There is a computer error. One of the position reference systems is unreliable. There is a thruster feedback error. There is a storm coming up.

On a Class 2 vessel with two boards what should be done if there is a blackout on one side?. Just close the tie breaker and keep working. Continue work and wait for approval from Charterer to stop work. Change to manual control as fast as possible. Don’t change to manual if vessel is holding position and move to safe location./Safely discontinue operation and leave working area.

Positioning using a Fanbeam reference system is not affected by: Direct light, such as rising/setting sun shining directly into the Fanbeam unit. Dense fog. Improperly secured tube reflection moving in strong winds. Interference from vessel`s radio transmissions.

Redundancy, with respect to vessel heading input can be achieved by fitting: 2 or more Motion reference unit. A third DP Operator Station. An extra DP Control Computer. 2 or more Gyro Compasses.

"Should there be a severe system failure, such as the total loss of position or heading input to the system, a software function will maintain thruster output settings. This function is called:". Model control or Dead Reckoning mode. Aerodynamic model. Thrust Allocation. Wind feed forward.

The best placement, when possible of an HPR system transponder beacon will be: Downwind and down-current from vessel location. down-current and upwind from vessel location. upwind and up-current from vessel location / On the opposite side to the tunnel wash. Downwind and up-current from vessel location.

The environmental forces acting on a DP vessel is said to be all the remaining forces acting on that vessel once the forces from one particular sensor has been taken into account, what sensor is this referring to?. Wind. Current meter. Gyro. MRU.

The DP current is determined by: Measurement of the water velocity from the ship`s Doppler log. Using thruster forces to determine velocity. Calculation using the mathematical model. Comparison of the vessel velocity from DGPS to the Doppler Log value.

The data taken into the DP mathematical model is a combination of calculated and real time forces, what is the real time force that is used?. Heave and pitch. The direction of the vessel moves. The speed of the vessel moves. The wind direction and strength in relation to the ship`s head.

The DARPS Position Reference System is one in which: A shuttle-tanker may position relative to a moving point such as an FPSO. Differential corrections are received and used to increase the accuracy of positioning. Relative positioning is obtained using a combination of GPS and laser-based systems. The vessel is allowed to weathervane whilst maintaining position.

The following Position Reference System configurations are available for a DP Class 3 operation. Which is the best configuration?. 2 DGNSS and Laser. Taut Wire and two independent HPR systems. DGNSS, Laser, Artemis and a single HPR system. DGNSS, Taut Wire and a single HPR system with two transponders.

The function of DP system Redundancy is to: Enable the vessel to continue operations subsequent to a single failure. Allow the Captain to sleep better. Allow the operation to be safely abandoned after any single-point failure. Allow vessel to use a higher set point speed.

The main purpose of Dynamic Positioning is to: Leave the positioning of the vessel to the computers in order that the operator on the bridge can be relieved of tedious work and focus on more important bridge. Maintain position and heading automatically. Maintain position, but not heading, automatically. Maintain heading, but not position, automatically.

The online Consequence Analysis function: Determines the risk in the OP-planning process. required for Class 1, 2, and 3 vessels. Verifies continued thruster and power redundancy for Of Class 2 and 3 vessels. Calculates the vessel's capability to hold position in various wind conditions.

The possibility of loss of Position and/or Heading is reduced by: Ensuring system redundancy to Equipment Class 2 or 3. Deploying multiple Position Reference Systems. Ensuring DP Operators are well-trained and experienced. Efficient and comprehensive operational planning.

The Sway is determined from data from: Position Reference Systems. Gyro Compasses. Vertical Reference Sensors. Draft sensors.

The thrusters on a DP vessel control: Heave, Pitch And Surge. Heave, Pitch And Sway. Yaw, Heave And Roll. Surge, Sway And Yaw.

The total amount of thruster force needed to maintain station in the auto-position mode vary: When gain settings on the DP system are adjusted. When generators are taken offline. When extra thrusters are brought online. If thruster fails to zero thruster.

The wind sensors are being fully blocked by the topside of platform. What should you do?. Remain in position and leave wind sensors selected. Suspend operations. Inform ETO. Move to windward side.

To understand the consequences of failure in any redundant part of a DP system onboard a DP 2 or 3 vessel, the DP operator should be familiar with: The International Maritime Organisation MSC/Circ 645 of 1994 Guidelines for Vessels with Dynamic Positioning Systems. Standards of Training, Certification and Watch keeping (STCW) Convention. Safety of Life at Sea (SOLAS) Convention. The Failure Modes and Effects Analysis (FMEA) documents.

Ultra Short Baseline (USBL) Hydroacoustic positioning is determined by: Acoustic ranging from multiple transponders in an array. Range and bearing of a single transponder beacon. Difference in time of arrival of signal from a single pinger beacon to an array of hydrophones mounted on the vessel hull. Monitoring signals from a mobile transponder beacon.

Under which of the following conditions may positioning be improved by increasing 'Control Gain'?. When station keeping is poor due to high noise in the position reference sensors. When thrusters appear to be 'hunting'. When encountering increased wind or current conditions. During periods of poor visibility.

Under which DP vessel Equipment Class is it possible that loss of position may occur in the event of a single fault?. Class 1. Class 2. Class 3. None of them.

What does the DP System use to calculate weighting (or confidence) for each Position Reference System?. Distance from the receiver. Signal strength. Weather conditions. Relative spread of fixes.

What is a vessel model?. A totally accurate description of a vessel's motions. A computer algorithm that calculates thruster set point signals. A mathematical description of how the vessel reacts to the forces acting upon it. A software routine continually monitoring redundancy level.

What is the meaning of DARPS?. Desirable Artemis Related Position System. Differential Artemis Relative Position System. Differential Absolute and Relative Position System. Degraded Absolute and Rigid Position System.

What is the purpose of the “Wind feed forward” facility?. To give operator an indications of the direction of the wind on DP operator display. It feeds the wind effect into the DP model to allow the vessel to hold position./Anticipating the wind force and correcting for it. Smoothing out peaks and troughs in wind data. It is used to calculate the leeway when the DP system is in track follow mode.

What is preferential tripping?. When the power management system trips off non-essential loads such as cabin air conditioning. When the power management system trips off navigational equipment. When the power management system trips off a thruster using bias mode. When the power management system trips off a thruster using the most power.

What is an FMEA with respect to a DP vessel?. A manual that gives instructions on the operation of the DP system. A document which highlights failure modes of the DP system and their effects on operation. Company procedures for carrying out DP operations. Emergency procedures to deal with DP failures.

What is the function of the Motion Reference Unit?. To measure Position. To measure Pitch, Roll and Heave. To measure Heading. To enable compensation for the wind force.

What is a vessel model?. A totally accurate description of a vessel's motions. A computer algorithm that calculates thruster set point signals. A mathematical description of how the vessel reacts to the forces acting upon it. A software routine continually monitoring redundancy level.

What is a drift test?. A drift test must be completed with thrusters turning in force bias condition. The vessel is stopped and allowed to drift outside 500 meters to ascertain the direction of drift. A drift test is calculating the drift using the tabulated current from the current tables. A drift test is done with active DP system at about 100 meters just prior to operations.

What is the main reason why DP equipment class 2 vessel requires at least 3 gyros`s?. One is for navigation and the other two are for DP. It provides the most accurate heading. If one is giving a wrong heading the DPO will know which one it is. It is required for triple redundancy.

What has a major negative effect on sound propagation in water when using an Hydroacoustic Position Reference (HPR) system?. Seabed topography. Thruster noise. Water pressure. Water salinity.

What is a Capability Diagram?. The capability of the ship concerning the DP-classes. A tool for estimating the position-keeping capability of the ship. The time interval for plotting the vessel's position on the screen. A history track of the vessel's positions showing the vessels offset.

What is one disadvantage of a ship working using its DP system compared to being anchored?. DP vessels are less maneuverable than a vessel positioning using anchors. Continually running thrusters are hazards for divers and ROVs. A DP vessel takes longer to move between work locations. A DP vessel can only work in very shallow water.

What determines the amount of thruster force used while operating in the joystick mode of operation?. wind force measurements. The number of generations on the switchboard. Joystick deflection and settings. vessel classification.

What is the minimum number of Thrusters required for a DP Class 2 vessel?. One bow and one stern Thrusters. Two bow and two stern Thrusters. Two bow and one stern Thrusters. Three bow and two stern Thrusters.

When using a Taut Wire positioning system, which of the following factors are significant?. Heavy rain can affect the accuracy of the Taut Wire system. The position of the vessel is related to the position of the work site./Accuracy deteriorates as water depth and/or angle of wire increases. The taut wire systems does not need power to operate. The taut wire systems are maintenance free.

When operating close to another DP vessel, potential mutual interference is likely from. Survey data reception. A reduction in GNSS signal strength. Acoustic PRS interference. Sun spot activity.

When using the HPR system, only ranges are measured in the following mode;. Ultra deep water. Long baseline. Short baseline. Ultra-short baseline.

When the electrical power demand from the thruster exceeds a set percentage of the online generating capacity what will happen?. The vessel will have a blackout of one switchboard. The vessel will drift because of lack of power. Electrical power for thruster will be reduced temporarily until additional generators are brought on line/Preferential tripping of non-essential loads if all generators are operational. / VESSEL OPERATIONAL AND TOTAL LOADS WILL BE REDUCED UNTIL ADDITIONAL GENERATORS ARE BROUGHT ON LINE. Thrusters will automatically be shut down to prevent a blackout.

When using a Hydroacoustic Position Reference (HPR) system, acoustic reception is not adversely affected by: Aeration in the water. Heavy snowfall. Thruster noise. Temperature layering in the water column.

When planning a DP operation for a location close to a fixed structure, one of the most important considerations is to: Check that all position reference systems are on-line. Determine the schedule of platform communications. Plan a reliable vessel escape route from the location. Complete a pre-operational checklist.

Which of the following inputs is required before surge or sway can be automatically controlled?. Wind Sensor. Vertical Reference Sensor. Power Management System. Position Reference System.

Which of the following include 4 of the 7 main elements of a DP system?. Safety equipment, thrusters, lifeboats and navigation lights. Thrusters, power supply, position reference systems and sensors. Loran, power supply, ballast system and thrusters. Sensors, stability calculator, position reference systems and magnetic compass.

Which of the following is NOT considered to be a 'Local' Position Reference System?. Hydro acoustic Position Reference (HPR). Taut Wire. Laser. DGNSS.

Which of the '6 degrees of freedom' for movements of a ship are controlled by the DP system?. Pitch, Roll and Heave. Roll, Surge and Sway. Swell, Heading and Heave. Sway, Yaw and Surge.

Which Position Reference System provides the DP system with a global position (i.e. Latitude and Longitude or UTM co- ordinates)?. FMCW Radar. Taut Wire. Laser. DGNSS.

Which is the system that uses a single transducer and a calibrated array of transponders located on the sea floor?. Long Baseline (LBL) acoustic positioning. Short Baseline [58] acoustic positioning. Super Shot Baseline (SSBL) acoustic positioning. Ultra Short Baseline (USBL) acoustic positioning.

Which of the following can cause wind model errors?. An incorrect estimation of the sea current. Selection of more than three wind sensors. Increased thruster activity. Locating the vessel in a position which is partly sheltered from the wind.

Which of the following affects the amount of thruster force used while maintaining station in the auto-position mode?. environmental forces acting on the vessel and excursion from set point, if any. vessel IMO Equipment Class and Lloyds classification. Number of position reference systems in use. The class of operation being conducted.

With the DP system set to the 'Auto Position' mode, the system will: Control the vessel's heading to achieve a minimum power configuration.manecer en la zona de comfort. Allow the DPO to manoeuvre the vessel using the Joystick control. Maintain the vessel's position and heading as closely as possible to the set-point values. Cause the vessel to automatically follow a predetermined track.

Why is it necessary for a vessel to be in Auto Position mode for a minimum of 30 minutes before starting work?. To allow the DPO to complete the pre-DP checklist. In order that additional position-reference systems may be enabled. To allow the system's mathematical model to build. To ensure that all thrusters are responding correctly.

Why may "Prohibited azimuth zones" or "azimuth barring" still be required when only one azimuth thruster is fitted?. To prevent interference with acoustic devices on the hull such as echo sounder and Doppler Log transducers. to prevent interference with tunnel thrusters. to allow access to the Azimuth Thruster in dry dock. To make life easy for the engineers.

For Equipment Class 3 vessels at least one of the PRS should be directly connected to which of the following?. The acoustic system. The backup control system and separated by an A-60 class division from the other position reference systems. The backup control system and independent of the position reference systems. The independent joystick which is separated by an A-60 class division.

How is Time to Terminate (TTT) calculated? (Ref: MTS) Responses. Time to Terminate (TTT) is calculated as the amount of time required to leave to 500m zone. Time to Terminate (TTT) is calculated as the amount of time required in an emergency to physically free the DP vessel from its operational activity following a DP abort status and allowing it to be manoeuvred clear and to proceed to safety. Time to Terminate (TTT) is calculated as the amount of time to restore the vessel after a blackout. Time to Terminate (TTT) is calculated by the consequence analyser and displayed on the operating station.

How long should DP fault logs be kept on board?. Records of all faults related to the DP system should be retained on board permanently. Investigation records and close outs should be retained on board for five years. Investigation records and close outs should be retained on board until the next class survey. Records of all faults related to the DP system should be retained on board until the next annual trials.

How long should DP familiarisation and competency records be kept on board?. All records relating to vessel-specific DP familiarisation and competency for key DP personnel including. DPOs and technical DP personnel be retained on board until the next annual trials. All records relating to vessel-specific DP familiarisation and competency for key DP personnel including DPOs and technical DP personnel be should retained on board for five years. All records relating to vessel-specific DP familiarisation and competency for key DP personnel including DPOs and technical DP personnel should be kept on board permanently.

How should vessels constructed prior to 9th June 2017 be treated with regards to their dynamic positioning systems and applicable IMO Guidelines?. IMO MSC 1580 Guidelines for Vessels and Units with Dynamic Positioning (DP) Systems overrides all previous regulation without exception. IMO MSC 645 issued 1994 applies. However it is recommended that section 4 of IMO MSC 1580 Guidelines for Vessels and Units with Dynamic Positioning (DP) Systems is adhered to. IMO MSC 645 issued 1994 applies.

How can redundancy be achieved?. By providing a second DP control computer and three position references as defined by the relevant classification society. By providing backup systems remotely located from the main DP console, e.g. in a DP back up room. By providing an independent joystick that is capable of maintaining the vessel heading and position. By installation of multiple components, systems, or alternative means of performing a function.

IMCA Station Keeping Bulletin 01/19 event 1 states "It is not good practice to have 4 DGNSS selected to the DP controller, this could result in rejecting other selected systems if the DGNSS were to drift due to a common satellite problem." What is the recommended mix of position reference system for a DP Class 3 dive support vessel operating at 200m?. 1 LBL acoustic array, 1 Artimis, 1 DARPS. 1 DGNSS, 1 USBL array, 2 DARPS. 2 DGNSS, 1 taut wire, 1 laser system. 2 DGNSS, 1 LBL acoustic array, 1 taut wire.

Mechanical wind sensors can lose speed cups or direction devices seize. What failure modes are known to affect ultrasonic wind sensors?. Induced noise in cabling systems, particularly from the vessel's MF antennas. Radio interference from GMDSS equipment is known to affect ultrasonic wind sensors and a distance separation of 10m is recommended from antennas. Periods of sunspot activity, eclipse and other celestial anomalies are known to cause disturbance to the sophisticated light phase shift measurement receiver. Rain, for instance during heavy squalls can cause an output loss.

On Equipment Class 3 vessels what should ONE of each type of sensor be connected to?. To the independent joystick. To the independent joystick and be separated by a A60 class division from the other sensors. To the backup DP control systems. To the backup DP control systems and be separated by a A60 class division from the other sensors.