Main Principles of the Passage Planning Process to Know


The oceans have always represented the primary artery of the global economy. However, this has never been more true than today. While oceangoing trade has always been important, modern navigation technology and organizational techniques have dramatically increased profitability. As a result, oceanic shipping makes up roughly nine-tenths of all international trade. Together with the rise in shipping rates, the risk of accidents has also risen. This is why modern navigation technology aims to minimize the possibility of human error. One way that the modern captain minimizes risk is by using an effective passage plan.

What is the Passage Planning Process?

Passage planning, also known as voyage planning, is the procedure a crew must comply with before relocating a ship from one mooring to another. It comprises a theoretical planning stage before the departure as well as a practical implementation stage during navigation.

The need for passage planning applies to all vessels in any type of voyage, including those under pilotage. Implementing a passage plan requires a thorough understanding of the underlying principles of the process. You can find these principles from two key resources, the SOLAS Convention and the IMO Resolution A.893-21.

More specifically, the legal framework concerning Passage Planning mainly consists of Chapter V of SOLAS Convention and IMO Resolution A.893-21. They describe the obligation to develop and implement such a plan as, "of essential importance for safety of life at sea, safety and efficiency of navigation, and protection of the marine environment." Accordingly, a passage plan is vital for successful ship relocation. Conversely, a defective or lacking plan can lead to serious legal consequences. A court could judge a crew negligent and find a shipowner's liability for lack of due diligence. This happened in a recent judgement by a British court.

The development and execution of a passage plan rely heavily on the ECDIS, for various reasons. In particular, ECDIS makes it easy to select saved routes and elaborate new ones. The planning graphic tool also assists planners by allowing them to quickly and efficiently modify routes. In addition, ECDIS facilitates precise, accurate measurements and calculations that it performs automatically. Since ECDIS plays such a large role in drafting a passage plan, the crew member in charge must understand electronic navigation.

Who is in Charge of Passage Planning

The legal responsibility for the passage planning process lies on the vessel's captain. In practice, the captain often delegates such duty to a Navigational Officer, or Officer On Watch (OOW). Navigational Officers (i.e. Captain, Chief Officer, Second Officer, or Third Officer) are essential players for successful onboard management. They exercise responsibility for the people, cargo and the vessel itself from port to port. These officers make important decisions on navigation, communication, general maintenance, day-to-day dock operations and overall ship operation.

The important role of ECDIS in Passage Planning is another reason that captains entrust Navigational Officers with this task. Generally, only they possess the necessary experience operating the ECDIS.

What Comprises a Passage Plan?

The passage plan must cover the voyage "berth to berth." This means it starts as the vessel leaves the dock and ends only after the ship completes mooring. Consequently, it also covers the distancing from the harbor area, the transit portion of the voyage and the approach to the final mooring.

The SOLAS Convention envisages passage planning as a four-stage process: appraisal, planning, execution and monitoring.

The Appraisal and Planning stages pertain to the theoretical development of the plan. On the other hand, Execution and Monitoring concern the practical implementation of the voyage.


This phase takes place before the beginning of the voyage. At this stage, the OOW must elaborate a detailed proposal of how he intends to conduct the passage. In doing so, he is to take a numerous set of factors into account, including:

  • The Captain's instructions (if any);

  • The eventual company's guidelines;

  • The marine environment;

  • Local regulations and warnings;

  • Weather forecasts (including tide and currents' predictions).

While performing this duty, the OOW will resort to a wide range of sources. These include:

The Appraisal stage will thus result in the provisional general track that the ship should follow. This, in turn, is the essential starting point to undertake the Planning phase.


The OOW has at this point collected all the necessary information within the Appraisal. Also, he proposed a general track to the captain. His next task in drafting a passage plan consists of planning the details of the voyage. The OOW will re-scale and lay down the track in the most suitable manner. The plan must also indicate areas of danger (e.g. landfalls, small islands, narrow passages, wrecks, reefs, No-Go Areas).

Additionally, planning requires the OOW to provide various forms of information that are relevant to the voyage. The purpose of this requirement is to ensure the safety of the crew, marine life, and to protect the marine environment. SOLAS considers this information necessary to ensure a safe, successful voyage.

This information includes:

  • Safe speed;

  • Necessary speed alterations en-route;

  • Minimum under keel clearance;

  • Necessary change in machine status;

  • Course alteration points;

  • Methods and frequency of position fixing;

  • Existing ships' reporting and routing systems and vessel traffic services;

  • Areas subject to marine environmental protection rules;

  • Contingency plans in case of emergency, safe anchorage points, aborts.

After the OOW has finalized the passage plan, the captain needs to approve it. At this point, the OOW enters the plan into electronic navigation instruments. These generally include a GPS unit and one of the following:


As the name implies, this stage corresponds to the crew's practical execution of the plan. Noticeably, the Resolution regarded this phase as an essential part of the passage planning process. This stresses how the captain must regard the plan as a living document. That is to say, he is under the obligation to review it and change it should unexpected circumstances arise. Examples of such circumstances include meteorological changes, natural hazards, visibility-related factors, traffic conditions and routing information.


This phase requires the crew to monitor the vessel's progress along the planned route. To do so, they employ standard methods including dead reckoning, celestial navigation, pilotage and electronic navigation. Parallel Index is also a useful tool to prevent the vessel from bumping into navigation hazards.

During the monitoring phase, the ship must promptly respond to any sudden change in circumstances that may arise. As a consequence, factors like experience, good seamanship and personal appreciation come to play a crucial role. For the same reason, the monitoring phase envisages the cooperation of a deck officer to achieve successful implementation.

Sign Up to Follow American Nautical

From appraisal and planning to execution and monitoring, the passage planning process is a vital step toward ensuring a safe voyage. When you follow the relevant SOLAS and IMO regulations, you're already closer to a successful voyage. If you want to keep up to date on the latest rules, regulations, technology and techniques, sign up with American Nautical. We strive to keep our readers up to date on all things pertaining to maritime transportation. Whether you're a hobby sailor or a veteran captain, we'll help you learn all you need to know to have a safe and successful voyage.