Editing Navigator (section)

== Mission and passage planning ==
{{Further|Passage planning}}
[[File:US Navy 080822-N-4044H-060 Quartermaster 2nd Class Carlos Oqendo plots points on the navigation chart aboard the guided-missile destroyer USS McFaul (DDG 74).jpg|thumb|200 px|[[USS McFaul (DDG 74)]] personnel using electronic systems and a navigation chart while she transits through the [[Turkish Straits]]]]
[[Image:Navigation system on a merchant ship.jpg|right|thumb|200px|Modern navigators often enter passage plans on [[electronic Chart Display and Information System|electronic systems]].]]

The navigator focuses on creating the ship's [[Passage planning|passage plan]]s (or "mission plans" for USAF purposes).  A mission or passage plan can be summarized as a comprehensive, step by step description of how the voyage is to proceed from berth to berth, including unberthing, departure, the en-route portion of a voyage, approach, and mooring/arrival at the destination.

Before each voyage begins, the navigator should develop a detailed mental model of how the entire voyage will proceed. In the aviation community, this is known as "chair flying".  This mental model includes charting courses and forecasting weather, tides, and currents.  It includes updating and checking [[aeronautical charts]],  [[nautical publications]], which could include [[Sailing Directions]] and [[Coast Pilots]], and projecting the various future events including landfalls, narrow passages, and course changes that will transpire during the voyage. This mental model becomes the standard by which the navigator will measure progress toward the goal of a safe and efficient voyage, and it is manifested in a written passage plan.

When working in a team environment, the passage/mission plan should be communicated to the navigation team in a pre-voyage conference (USAF term is "mission briefing") in order to ensure that all members of the team share the same mental model of the entire trip.

Passage planning procedures are specified in [[International Maritime Organization]] Resolutions, in the laws of IMO signatory countries (for example, Title 33 of the U.S. [[Code of Federal Regulations]]), and a number of professional books and USN/USAF publications. There are some fifty elements of a comprehensive passage plan depending on the size and type of vessel, each applicable according to the individual situation.

A good passage plan will include a track line laid out upon the largest-scale charts available which cover the vessel's track.  The navigator will draw and redraw the [[Course (navigation)|track line]] until it is safe, efficient, and in line with all applicable laws and regulations.  When the track is finished, it is becoming common practice to also enter it into electronic navigation tools such as an [[Electronic Chart Display and Information System]], a [[chartplotter]], or a [[GPS]] unit.

Once the voyage has begun the progress of the vessel along its planned route must be monitored. This requires that the ship's position be determined, using standard methods including [[dead reckoning]], radar fixing, [[celestial navigation]], [[pilotage]], and [[electronic navigation]], to include usage of GPS and navigation computer equipment.

Passage planning software, tide and tidal current predictors, celestial navigational calculators, consumables estimators for fuel, oil, water, and stores, and other useful applications.