Dynamic Positioning 

Our Dynamic Positioning service encompasses a comprehensive range of services essential for ensuring the reliability, safety, and efficiency of Dynamic Positioning (DP) systems on vessels.

It is a requirement from classification societies for a DP-capable vessel to be surveyed, tested and audited periodically to ensure the reliability of the Dynamic Positioning system and the group of components it encompasses. Such audits also take into consideration the management of DP operations and maintenance of related machinery and equipment/systems.

The only international marine regulations are written and published by the International Maritime Organization (IMO), who are a specialised branch of the United Nations. They published the latest DP guidelines in 2017, in a document called ‘Guidelines for Vessels and Units with Dynamic Positioning (DP) Systems’. Classification societies use this document to develop their own rules for Dynamically Positioned ships.

For full details of our specific Dynamic Positioning services, click the links below:

DP FMEA Proving Trials
ASOG, CAM and TAM – Operational Activity Planning
DP Annual Trials
eCMID, eMISW and OVID

Typical marine vessels making use of Dynamic Positioning systems include:

ROV support vessels, Diving Support Vessels (DSVs),  Platform supply vessels (PSVs), Semi-sub mobile offshore drilling units (MODUs), Drill ships, Crane Vessels, maritime research vessels, marine survey ships, scientific research vessels, wind farm service vessels, pipe laying vessels, cable laying vessels, rock dumping vessels, shuttle tankers, semi-sub flotels and mega yachts.

DP FMEA Proving Trials

Failure Modes and Effects Analysis (FMEA) is a systematic approach used to identify potential failure modes within a DP system and their consequences. Writing a DP FMEA Proving Trials document involves a detailed analysis of all components and subsystems to ensure that any single point of failure does not result in a loss of position. Proving trials are conducted to validate the FMEA, ensuring that the DP system performs as expected under various failure scenarios. These trials are meticulously planned and executed to test the resilience and redundancy of the DP system.
 

DP Annual Trials

DP Annual Trials are essential to verify the redundancy concept remains intact. Vassallo Associates undertakes these trials to test all critical aspects of the DP system, including sensors, thrusters, and power management systems.
 

5-Yearly DP FMEA Periodic Trials

A periodic DP trial is conducted at intervals of no more than five years (and multiples) from the proving trials. Although there might be a few omissions, this replicates the majority of the tests in the proving trials. For instance, exploratory tests to verify that a piece of equipment belongs to a specific redundant group do not need to be repeated because the relationship does not change with time unless modifications have been made.
 

DP Operations Manual Compilation

A DP operations manual is a crucial document that outlines the procedures, guidelines, and best practices for operating the DP system. Compiling this manual involves collaboration with vessel operators to document standard operating procedures, emergency response plans, and system limitations. This manual serves as a vital reference for DP operators, ensuring consistent and safe operation of the DP system.
 

Consultancy on Conversions & Upgrades from DP-1 to DP-2 and DP-2 to DP-3 (Including Gap Analysis)

Upgrading a vessel’s DP system from Dynamic Positioning 1 to Dynamic Positioning 2 or Dynamic Positioning 3 involves significant technical modifications and enhancements. Vassallo Associates conducts a gap analysis to identify the differences between the current system and the desired upgrade level. We provide detailed recommendations ensuring that the vessel meets higher redundancy and reliability standards required for more complex operations.
 

IMCA eCMID Audits

The International Marine Contractors Association (IMCA) provide a standardised vessel inspection in the form of the common marine inspection document, which is only available to accredited vessel inspectors. Vassallo Associates surveyors are all IMCA-accredited eCMID Inspectors.
 

Incident Investigations Related to DP Failures

When a DP failure occurs, a thorough investigation is required to determine the root cause and prevent recurrence. DP consultants lead these investigations, analysing data, interviewing personnel, and examining system components. They provide detailed reports with findings and recommendations to enhance system reliability and prevent future incidents.
 

Expert Witness

In legal proceedings related to DP system failures or maritime accidents, Vassallo Associates can serve as expert witnesses. Our expertise and experience provide critical insights into the technical aspects of DP operations, helping courts understand the complexities involved and making informed decisions.

Frequently Asked Questions

(Please note that these are concise answers and not fully comprehensive.)

What is Dynamic Positioning?

Dynamic Positioning (DP) is the operation of maintaining a vessel’s position and heading by computerised control of thrusters and propellers.

What is a DP System?

The complete installation necessary for dynamic positioning, comprising power generation, propulsion and control.

What are the DP Equipment Classes?

DP 1 is a non-fault tolerant DP system.
DP 2 is a fault tolerant DP system, where the vessel will maintain position and heading after any single failure.
DP 3 is fault tolerant system which meets DP 2 requirements, plus the vessel can maintain position after the loss of all the equipment in any one compartment due to fire or flooding.

What is redundancy concept?

The ability of a system to maintain its function after a single failure has occurred, usually achieved by duplication of equipment.

What are DP trials?

Annual trials

A series of tests to ascertain if the whole system is functional, and in the case of DP 2 and 3, if the redundancy concept remains intact.

Periodic trials

5 yearly trials, tests to check the vessel has redundancy for all the single failures described in the FMEA. Similar in content to proving trials and more comprehensive than annual trials.

Proving trials

Tests on a new vessel to check the DP system is as described in the FMEA.

CAM

Critical activity mode, which is the most fault tolerant setup of machinery and equipment.

TAM

A setup which is not a CAM, but may be suitable for some operations.

ASOG

Activity specific operating guidelines, a table listing operating parameters, including equipment in use, weather, thruster loads etc, and advice on action to take when the parameters are exceeded. An easy and quick look up decision support tool.

FMEA

Failure mode and effect analysis, a description of the entire DP system, power, propulsion and control. It states the redundancy concept, describes the worst case failure design intent, and analyses the failure modes of each system to check if the redundancy concept is valid. It is checked by testing every system during the proving trials.

What is a DP Operations Manual

A description of the DP system, operating guidance in various situations and conditions, DPO qualification and experience, responsibilities etc.

What is eCMID?

Standard form produced by IMCA for checking the vessel’s safety management system. The form can only be downloaded by accredited vessel inspectors.

What is eMISW?

A reduced-size eCMID for small workboats under 500 GRT.

What is OVID?

Offshore vessel inspection database, a standard form produced by OCIMF recording a vessels details, safety performance and environmental record, which is uploaded to a database and can be viewed by registered users, usually oil company charterers. It can only be downloaded by registered inspectors.

We operate from offices based in London and Malta, however, we can travel nationally and internationally to provide client support.