DP CPD

What is the primary function of a DP system's consequence analysis feature?. To predict fuel consumption. To assess the impact of a single point failure on position keeping. To optimize crew schedules. To calculate voyage duration.

According to IMCA M 117, how often should DP trials be conducted?. Every 5 years. Annually. Biannually. Only after major repairs.

What is the significance of the term "DP footprint"?. The physical size of the DP control console. The area over which the vessel can safely operate under DP. The environmental impact of DP operations. The number of crew required for DP operations.

Which component provides real-time data on vessel motion for DP systems?. Gyrocompass. Wind sensor. Motion Reference Unit (MRU). Echo sounder.

What does the term "common mode failure" refer to in DP operations?. A failure affecting multiple systems due to a shared cause. A standard operational procedure. A typical weather-related issue. A common training module.

In DP operations, what is the purpose of a "blackout recovery test"?. To test emergency lighting. To assess the vessel's ability to recover DP operations after a power loss. To evaluate crew response to power outages. To check battery backup systems.

What is the role of the DP Operator (DPO) during critical operations?. Supervising deck maintenance. Monitoring and controlling the DP system to maintain vessel position. Monitoring and controlling the DP system to maintain vessel position. Overseeing cargo loading.

According to the Keelson DP Primer, what is the recommended minimum number of independent Position Reference Systems (PRS) for DP Class 2 vessels?. 1. 2. 3. 4.

What is the function of a gyrocompass in a DP system?. What is the function of a gyrocompass in a DP system?. Determining vessel heading. Calculating water depth. Monitoring fuel levels.

What does the term "thruster redundancy" mean in the context of DP systems?. Having extra crew members. Having additional thrusters available in case of failure. Using thrusters for propulsion only. Minimizing thruster usage.

What is the primary function of the DP vessel model used by control computers?. Determine fuel consumption. Simulate generator load. Predict vessel response to thrust and environmental forces. Measure satellite strength.

Which position reference system (PRS) is considered most accurate for short-range operations?. DGNSS. HPR. Laser-based system (e.g., Fanbeam). MRU.

What is the recommended DP mode for a vessel performing diving operations?. Manual thrust control. Joystick mode. Auto Position mode under CAM. Standby mode.

Which parameter does not directly affect DP system thrust calculations?. Wind speed and direction. PRS position fixes. Vessel heading. Crew roster.

What defines “worst-case failure” in DP systems?. The most fuel-consuming operation. The loss of the most significant component or system that could impact position-keeping. Temporary PRS drift. Loss of crew communications.

What feature helps prevent excessive thrust application in response to short-term PRS noise?. Thruster limiter. PRS latency. Sensor filtering. Wind feed forward.

What is the impact of a biased wind sensor?. Improved heading control. Thrust application in the wrong direction. Higher satellite lock. No impact.

How does a DP system respond if the MRU data stream is lost?. Increases gain. Switches to manual. Alarms the DPO and removes motion compensation from PRS. Uses radar for motion input.

What is the DP system's default response to a failure in a Class 2 vessel during operations?. What is the DP system's default response to a failure in a Class 2 vessel during operations?. Reallocate remaining thrust to maintain position. Switch to joystick. Call the port authority.

Which condition requires the DPO to switch from TAM to CAM?. Vessel enters port. Start of critical operations such as diving or pipeline touchdown. Crew change. Engine RPM check.

What is the main reason to use different types of PRS (e.g., GNSS, HPR, laser)?. Reduce training cost. Improve GNSS signal lock. Reduce common mode failure risk. Prevent gyro drift.

What is an acceptable response if the DP system enters Yellow Alert during operations?. Stop all activities immediately. Assess system status and risk, continue if redundancy is adequate. Disconnect all PRS. Increase gain.

Which failure does the DP system’s Consequence Analysis tool simulate?. Fuel tank rupture. Heading offset. Worst-case failure (e.g., generator or thruster loss). Gyro warm-up.

What happens if a laser PRS loses visual contact with its target?. Thrusters shut down. The system alarms and may de-select the PRS. It switches to HPR. Wind speed increases.

What is the primary benefit of Feed Forward control in DP?. Predict environmental disturbances and pre-emptively apply thrust. Remove GPS drift. Shut down PRS during operations. Increase heading deviation.

What does the Power Management System (PMS) protect the DP system from?. Satellite dropout. Thruster blockage. Overload and blackout conditions. Anchor drag.

What is the role of the DPO during environmental changes such as increased wind?. Reset the DP system. Stop operations immediately. Monitor system performance and prepare to modify mode or heading. Change crew shift.

What causes common mode failure among GNSS receivers?. Crew error. Shared satellite or correction service failure. Different antenna heights. Rain.

What is the purpose of the DP Alert status indicator (Green/Yellow/Red)?. Show thruster temperature. Provide real-time redundancy status. Show MRU alignment. Count PRS used.

What should a DPO do before engaging DP for a complex operation?. Call the chief cook. Verify system health and confirm setpoint readiness. Reset all sensors. Disable MRU input.

Which DP failure scenario is most serious during diving operations?. Satellite jitter. Loss of heading. Drift-off due to thrust loss. Thruster overheating.

How does filtering help DP system sensor input?. Removes essential data. Enhances operator visual display only. Reduces noise and jitter from raw data. Slows down position updates.

What is the Keelson-recommended method for ensuring PRS diversity?. Install 3 DGNSS units. Use only HPR. Combine DGNSS with laser and acoustic PRS. Use 2 radar units.

In DP terms, what is “yaw”?. Sideways motion. Forward motion. Rotation around the vertical axis. Vertical motion.

What happens when the DP system detects an MRU data drop?. Improves accuracy. Switches to joystick. Removes motion compensation from PRS and alerts DPO. Updates GPS faster.

What is the expected action after a power system FMEA identifies a failure not survivable in CAM?. No change. Switch to manual mode. Reconfigure power and notify DPO before re-entering CAM. Increase fuel load.

Which sensor data is most affected by thruster aeration?. MRU. HPR (acoustic PRS). DGNSS. Gyro.

What is the typical consequence of an unplanned mode change e.g., Auto to Joystick)?. Vessel improves fuel economy. System stabilizes automatically. Sudden position shift or loss of station. Alarms decrease.

What does a tight DP footprint indicate?. High environmental forces. Excellent station-keeping performance. Poor PRS health. Weak gain setting.

What defines the effectiveness of a laser PRS in operations?. Thruster angle. Line-of-sight availability and stability. Fuel type. Gyro orientation.

What is the purpose of a DP Capability Plot?. To show fuel efficiency based on thrust usage. To illustrate vessel stability during heavy weather. To display the environmental conditions the vessel can withstand while maintaining position, before and after failure. To track crew performance during operations.

What operational guideline document must be followed for each critical DP task?. ISPS Code. ASOG (Activity Specific Operating Guidelines). SOLAS Chapter II. MARPOL Annex V.

Which condition is most likely to affect acoustic PRS (e.g., HPR) accuracy?. Fog. Solar flares. Thruster-induced turbulence and aeration. Heading deviation.

What is the term for an automatic system's tendency to overreact to minor input changes?. Thruster interaction. Gain lag. Hunting. Pitch damping.

What should the DPO verify during a DP system handover between operators?. The name of the new operator. Heading control only. System status, alerts, sensor validity, and redundancy. Galley status.

Why is heading stability important in DP operations, even if position is maintained?. It improves vessel aesthetics. It reduces gyro wear. It ensures valid use of PRS data and correct environmental modeling. It increases radar accuracy.

What is a likely indicator of a poorly tuned DP control loop?. Stable footprint. Constant low power usage. Frequent small heading or position corrections (hunting). GPS dropout.

Which class of DP system requires full physical separation of redundant components?. Class 1. Class 2. Class 3. Unclassified.

Which sensor does the DP system use to maintain automatic heading control?. Wind sensor. MRU. DGNSS. Gyro compass.

What action should a DPO take if the DP system reverts unexpectedly to Joystick mode?. Increase gain. Notify port control. Investigate and confirm system integrity, revert to Auto Position only if safe. Ignore unless vessel moves.

What is a key requirement for switching from TAM to CAM mode in DP operations?. Switching from GNSS to laser PRS. Activating a power save mode. Verifying system redundancy meets the worst-case failure criteria. Setting the radar gain to low.

In DP systems, what does “surge” describe?. Side-to-side motion. Movement along the longitudinal axis (forward/backward). Rotation about the vertical axis. Vertical up/down motion.

What is the effect of placing a wind sensor too close to a crane or tower?. Enhanced wind readings. Wind direction reversal. Distorted wind data due to turbulence and sheltering. Increased battery life.

What is the purpose of the Activity Specific Operating Guidelines (ASOG)?. Define onboard training procedures. Document voyage plans. Provide task-specific guidance for DP operations, including failure responses. Track fuel consumption.

Which of the following environmental factors most affects GNSS PRS accuracy?. Salinity. Wave height. Ionospheric delay and multipath error. Moon phase.

What is the DP system’s typical response to detection of a failed thruster during Class 2 operation?. Shutdown of entire thrust system. Continue operating using remaining thrusters. Reboot the DP control system. Notify class society.

What component is essential to allow PRS to be corrected for vessel motion?. Wind sensor. MRU (Motion Reference Unit). Gyro compass. Radar.

What type of failure is simulated during DP Annual Trials using consequence analysis?. Hull breach. Generator failure, thruster loss, or control loss. Fire detection test. Fuel contamination.

Which of the following is a benefit of having three different types of PRS in use?. Reduced cost. Lower MRU drift. Elimination of sensor tuning. Ability to cross-check and reject faulty data confidently.

What is the main function of the DP control computer?. Process sensor input, compare it to the setpoint, and adjust thrust accordingly. Calculate vessel trim.

In DP, what is “heave”?. Sideways motion. Vertical up/down motion. Heading change.

What may happen if two PRS systems produce similar but incorrect data due to shared failure?. Better accuracy. Loss of position redundancy. System prioritizes them automatically. Reduced fuel use.

What defines a system's ability to recover from power loss in DP?. Presence of solar panels. Automatic backup crew. UPS systems and DP system restart protocols.

Which parameter is NOT provided by the MRU?. Pitch. Roll. Heading. Heave.

What is the main operational risk of hunting behavior in thruster output?. Reduced motion control. Wasted energy, unnecessary thruster wear, and reduced fuel efficiency. Slower GPS updates. Crew seasickness.

What operational task must be completed before engaging in DP for any critical activity?. Logbook signing. MRU recalibration. DP system pre-task check and CAM configuration verification. Weather report printing.

What is the purpose of Deadband in the DP control system?. Delays gyro initialization. Limits minor adjustments to avoid unnecessary thrust action. Pauses wind sensor updates. Prevents radar update lag.

What environmental sensor input is required for Feed Forward control?. Radar. Wind sensor. MRU. Laser PRS.

Which of the following is NOT a valid relative positioning method?. Taut wire. Fanbeam (laser). HPR. DGNSS.

In the event of a generator failure during DP operations, what is the expected action from the PMS?. Increase gain on all sensors. Switch to joystick mode. Shed non-essential loads and engage backup generators to protect DP. Stop MRU input.

Why is it important to define the vessel’s center of rotation in the DP system?. Affects wind sensor height. Adjusts MRU calibration. Ensures accurate thrust application for heading and movement. Defines crew sleeping quarters.

What is the most significant operational risk if PRS filtering is set too high?. System becomes too responsive. Increased MRU range. Slow reaction to real position changes. Better energy efficiency.

Why does Keelson recommend full PRS health checks before DP operations?. To satisfy flag state inspections. To update power management software. To validate signal quality, stability, and redundancy. To reduce crew workload.

Which of the following is a valid reason to reject a PRS during DP operations?. It shows an increasing error trend or fails the median test. The DPO dislikes it.

What does Keelson identify as a primary cause of footprint instability?. Old radar systems. Crew shifts. Incorrect environmental model or gain settings. Taut wire length.

In DP, what does the abbreviation CAM stand for?. Centralized Alert Management. Critical Alert Mode. Critical Activity Mode. Common Area Mode.

What is the role of TAM (Task Appropriate Mode) in DP?. Used only when heading is unstable. Used during low-risk DP tasks with relaxed redundancy requirements. Applied to track vessel speed. Used only when entering port.

What is “gain” in a DP system?. Power available to each thruster. A control parameter that determines the system's responsiveness to errors. A filter used on PRS signals. A backup battery setting.

Which factor is most important for correct DGNSS performance?. Vessel heading. Correction signal quality and satellite geometry (HDOP). Antenna color. Radar alignment.

What is a median test used for in DP systems?. Adjusting fuel mix. Comparing sensor inputs to identify outliers. Testing MRU calibration. Rebooting the DP console.

What does PRS dropout typically result in?. Improved positioning. Gyro recalibration. Decreased confidence and potential loss of redundancy. More accurate wind readings.

What would an unexpected spike in thrust without corresponding vessel movement likely indicate?. Sensor alarm. Environmental model error. MRU battery fault. Heading change.

What is the main reason to keep a PRS well-separated from other equipment on the vessel?. Safety from high-pressure water. Improve visual appearance. Minimize electromagnetic or acoustic interference and allow independent. Balance vessel trim.

What effect does low gain have on the DP system’s behavior?. Rapid corrections. Overheating of sensors. Delayed response to positional deviation. Sudden heading changes.

What is a PRS confidence level?. Crew rating of the sensor. Percentage of expected satellite correction. System-generated measure of sensor reliability based on recent performance. Battery voltage of the sensor.

Which scenario best defines a Class 3 DP system’s purpose?. Light cargo transfer at port. High-risk operations like diving with fire/flood redundancy. Towing vessel for offshore anchoring. Small passenger ferry.

What typically causes a drift in gyro compass heading?. Tidal shifts. Poor PRS alignment. Internal sensor error or warm-up instability. Thruster vibration.

Which condition indicates a stable footprint?. Tight clustering of position points around the setpoint. Long tail patterns behind the vessel. Expanding spirals. Random wide dispersion.

What must be verified before switching into CAM for a critical operation?. Anchor position. ASOG compliance and system redundancy against WCFDI. MRU firmware version. Wind direction.

What would likely trigger a transition from Green to Yellow DP Alert status?. PRS de-selection or generator fault. All systems nominal. Vessel turns into wind. Radar detection loss.

How does the DP system detect a faulty PRS?. Based on operator feedback. Using signal latency. Via statistical tools like median test, residual analysis, or spread thresholds. Randomly.

What is an appropriate DPO action if an MRU fails mid-operation?. Stop PRS input. Continue without action. Switch to manual mode or reduce operation scope based on ASOG. Reduce heading setpoint.

What is the effect of strong side winds with the vessel bow-on to current?. Minimal effect. Increased yaw moment and potential heading loss. Reduced fuel consumption. Better PRS confidence.

What is the DP system’s response if power is lost to one of its control computers?. Switch to backup control system if redundancy is intact. Abort operation immediately. Switch to radar-only navigation. Increase PRS gain.

Which condition most likely causes acoustic noise affecting HPR performance?. Calm water. Wind shift. Thruster wash and cavitation. Satellite handover.

What is the risk of setting the DP system’s PRS weighting manually without validation?. Increased heading accuracy. System shuts down. Incorrect prioritization of faulty inputs. Better redundancy.

How is the DP setpoint established before starting an operation?. Random selection. Crew consensus. GPS fix combined with heading value from gyro. Average of past vessel tracks.

Why is redundancy across power supplies essential for DP?. To allow use of backup printers. To reduce generator fuel. To ensure power continuity for all critical systems after failure. To boost wind sensor performance.

What indicates a potential common mode failure across PRS inputs?. One PRS fails silently. All PRSs show identical but clearly incorrect data. Loss of MRU. No PRS data change during heavy weather.

What is the final DPO responsibility when a DP alarm sounds?. Silence the alarm. Ignore it if operations are stable. Acknowledge the alarm, identify the source, assess its impact, and act in line. Immediately call class society.