Page 17: of Offshore Engineer Magazine (Mar/Apr 2022)

16 18

OPERATIONS DYNAMIC POSITIONING he single most important redundancy element and that needs to be changed. The position trace contains in a dynamic positioning (DP) system is the dy- valuable information about system operation and the DP namic positioning operator (DPO). DP systems station needs to monitor related systems to quickly detect

T have become so reliable that some vessel opera- and con? rm problems. DPOs need to take time to absorb tors and clients have forgotten the purpose of the DPO. the unique properties of their vessel.

High reliability leaves many operators unprepared for fun- DPOs don’t get to simulate faults during regular opera- damental failure modes and causes costly failures. tions, so annual trials are an important reminder of what

This is dangerous because DP systems are not actually some failure modes look like. Failure to maintain position redundant and still depend on the human operator to en- or heading may indicate regular training or design changes sure safe operation. The design assumption is still that the are needed to manage what used to be a common fault.

DPO is ready to spring into action. This was truer when Failure to maintain position after the failure of the DP sys- operators had to regularly correct DP system faults, but tem is usually due to unfamiliarity with the IJS. Too many as the systems became more and more reliable, DPOs DPOs can’t do this. A DPO who can’t, isn’t really a DPO, had dif? culty recognising early fault indications and re- as he cannot perform a crucial expected function. Every sponding properly. The airline industry refers to this as the DPO should be regularly drilled on resolving their vessel’s “bored-person-in-the-control-loop” problem. fundamental failure modes.

Some people propose regular simulator testing for DPOs are vital to vessel redundancy. The staf? ng and this. Simulator training is highly effective in the aircraft culture need to re? ect this. DPOs are not doing nothing, industry because the controls and response of a particu- and should not be distracted with other tasks, they are lar plane model are identical. Pilots that will operate a critical to ensuring safe DP operation. Operations need to different model of aircraft or updated software need to recognize their tasks’ importance and keep them ready for be trained on it. A lack of familiarity with slightly differ- action. They should be system and vessel experts, not re- ent controls or response has caused numerous accidents placeable cogs that an operator is forced to employ. in the airline industry. In the marine industry, controls, Unfortunately, even the best people make mistakes or vessel propulsion and vessel response vary widely from have bad luck. Good management recognizes this, accepts vessel to vessel and over time. Marine simulators are the possibility of failures and minimizes their probability. a good start for learning basics but not for drilled re- Some people are unsuitable for DPO work, regardless of sponse. Continuous training on each orphan vessel pro- paperwork, and need to be detected and ? ltered out. Certi- duces better results. ? cation, book learning, simulator training and experience

This doesn’t have to be dif? cult. DPOs should help train elsewhere are not the same as ingrained, active, vessel spe- each other. Can the operator reliably ? nd the controls with ci? c, system understanding. his eyes closed? Can he draw them from memory and dis- In the old days, crew were given busy work so they got cuss possible dangers to operation? Do they double check used to the vessel and able to detect problems not found their actions? Do they discuss normal and emergency op- by sensors. Today, such actions are considered inef? cient. eration and try to keep each other sharp with what if sce- Today’s operators have more sensors but it is still very im- narios? These help ensure reliable operation and reinforce portant for them to develop an intuitive, vessel speci? c feel their importance. This used to be common and it needs to for the movement, response and sounds of their vessel, and be encouraged. its interaction with the environment and mission.

Operators need time to “play” with equipment to get a Remote micromanaging, by some managers, consul- feel for the whole system and its functions. The increased tants, clients and industry bodies, undermines real DPO familiarity pays off when something goes wrong. DPOs responsibility and initiative. Cogs perform sub-optimally who only operate the independent joystick system during and maximize trouble avoidance, while an active and re- annual trials are not likely to be skilled with it, despite it sponsible DP culture covers more than just procedures. being a fundamental part of their job. 15 minute DPO DPOs should be encouraged to evaluate and adopt im- check sheets were used to aid the DPOs in being ready provements themselves. It is easy to in? ict answers but to anticipate, catch and correct problems. Some vessel DP more effective to encourage them. Standards must be desks are set up to look pretty rather than detect problems maintained but how they are maintained sends a message. march/april 2022 OFFSHORE ENGINEER 17