1. Introduction — what planning is and the two stages
Once the appraisal has gathered the information and weighed the risks (Chapter 2), planning turns the master's decisions into marks on the chart. The book splits planning into two stages — and warns that in practice the two will often merge and overlap:
Source: SWIFT, A. J.; BAILEY, T. J. Bridge Team Management: a practical guide. 2nd ed. London: The Nautical Institute, 2004. Chapter 3 — Passage Planning (pp. 16-37).
Edital: Anexo 2-B, Área III, item 1 (Swift & Bailey) → Chapter 3 — Passage Planning · Anexo 2-A, Área III, item 10 (Planejamento de derrota em águas restritas / Passage planning — núcleo do tópico), conexão item 12 (prático a bordo; wheel-over mostrado mesmo com o prático no comando).
| Stage | Waters |
|---|---|
| 1 | Ocean and open waters. |
| 2 | Coastal and estuarial waters. |
The whole plan is built on paper charts first — every constraint decided at the appraisal stage is now drawn, highlighted and annotated so that the OOW on watch can read his situation at a glance, without re-deriving it under pressure.
2. Charts — assembling and correcting the outfit
Collect all the charts for the intended voyage and put them in the correct order. Include charts that are not absolutely necessary but lie adjacent to the area to be traversed, and the very large-scale charts such as port plans on the coastal part — they may carry information useful during the voyage even if never actually worked on.
Every chart and publication must be corrected to the latest Notice to Mariners available, and any authentic Nav warnings from any source must be included (see Annex II). Corrections may also arrive after the plan is finished, forcing the plan to be modified later.
Ensure that all charts and publications have been corrected to the latest Notice to Mariners available and that any authentic Nav warnings etc. received from any source are also included. — Swift & Bailey, Chapter 3 (Charts)
3. No-Go Areas — where the ship cannot go
The first marks on the coastal and estuarial charts define the no-go areas: every area where the ship CANNOT go is shown by highlighting or cross-hatching, taking care not to obliterate a navigation mark or a conspicuous object underneath. In waters with a small tidal range, a no-go area covers all charted depths less than the ship's draught plus a safety margin.
Because the margin depends on draught, no-go areas are not the same for the inward and outward passages. In confined waters where tidal height matters greatly, no-go areas vary with the time of passage: initially treat everything shallower than draught + margin as no-go, then amend once the actual transit time is known — marking clearly the times and state of tide at which each area becomes safe.
4. Margins of Safety and Safe Water
Before tracks are drawn, the clearing distance from the no-go areas must be settled. A plotted fix represents the position of one part of the ship — the bridge — at the moment of the fix. On a large ship the bridge fix can be outside a no-go area while another part of the hull is already inside it, with disastrous results. The margin of safety is a buffer around the no-go area set so that, in the worst probable circumstances, the part being navigated (the bridge) will not pass it.
| # | Factor |
|---|---|
| 1 | The dimensions of the ship. |
| 2 | The accuracy of the navigational systems to be used. |
| 3 | Tidal streams. |
| 4 | The manoeuvring characteristics of the ship. |
The margin must be chosen so it can be readily monitored — tied to a navigation system actually in use, e.g. clearing bearings to a headmark, or Parallel Indexes. It shows how far the ship can deviate and still stay in safe water.
Safe Water is the area inside the margins where the ship may safely deviate; its limits are the margins of safety.
5. Drawing the tracks
Tracks are now drawn within the no-go / safe-water framework, in two passes.
5.1 Ocean and open-water tracks
Draw these first on small-scale charts, following the route decided at appraisal. Great circle and composite great-circle tracks are calculated, taken from GPS, or obtained from great-circle charts. Rhumb lines may be drawn straight onto the Mercator chart — but every track must conform to the limits set at appraisal.
5.2 Coastal and estuarial tracks
Also constrained by the appraisal decisions, drawn first on small-scale charts covering large stretches of coast, ideally from the departure approaches to the arrival port (often more than one chart). These first tracks are the basis of the plan: from them come distances, steaming times and, once the departure time is known, the ETAs at each waypoint.
The true direction of the track is shown close to it on the chart. This is the direction to make good — not necessarily the course to steer, which depends on tidal set and drift, leeway, etc. at the time. When finished, the tracks are transferred to the large-scale charts of the area, an operation that must be done with great care.
5.3 Chart change
The position at which to transfer to the next chart must be shown clearly on the chart, giving the next chart's number.
5.4 Track consideration and distance off danger
As a rule there is nothing to gain by closely approaching a danger except shorter distance and steaming time. The ship must always stay in safe water and keep far enough off a danger to avoid grounding after a machinery breakdown or navigational error. There are no hard-and-fast rules for distance off; it depends on:
| # | Factor |
|---|---|
| 1 | Draught of the ship relative to the depth of water. |
| 2 | Weather prevailing — a strong onshore wind, or likely fog/rain, needs a bigger distance. |
| 3 | Direction and rate of the tidal stream or current. |
| 4 | Volume of traffic. |
| 5 | Age and reliability of the survey on which the chart is based. |
| 6 | Availability of safe water. |
| Situation | Pass |
|---|---|
| Steep-to coast (soundings increase quickly) | minimum 1½ – 2 miles off. |
| Coast shelves gradually — draught < 3 m | outside the 5 m contour. |
| draught 3 – 6 m | outside the 10 m contour. |
| draught 6 – 10 m | outside the 20 m contour. |
| draught > 10 m | ensure sufficient UKC; exercise due caution within the 200 m line. |
Ideally the ship follows the planned track; any deviation (e.g. altering for another ship) must be limited so the ship does not enter areas of risk or closely approach the margins of safety.
6. Under-keel clearance, tidal window and streams
A ship may be required to navigate with a reduced UKC; this must have been planned for and clearly shown. Where the UKC is less than 10% of the deepest draught (or whatever percentage was agreed at appraisal), the OOW must be made aware of it — and that speed may have to be reduced to cut squat and its consequent increase in effective draught.
6.1 Tidal window
In tidal areas, adequate UKC may exist only while the tide is above a given height. Outside that period the area is no-go. This safe period — the Tidal Window — must be shown clearly so the OOW has no doubt whether it is safe to proceed.
6.2 Stream allowance
In open sea, track correction is often made after the stream has set the ship off track. That is fine offshore, away from danger; but as the track approaches the coast it is better to correct for tide and current before they take effect. Current data (set and rate) is often on the chart, with more detail in Ocean Passages for the World, Routeing Charts and Pilot Books (Appraisal §§ 3, 4, 5). Tidal data comes from Charts, Tide Tables and Tidal Atlases, with local detail in Pilot Books (Appraisal §§ 5, 7, 8). Streams vary with the time of HW and the phase of the moon (neaps and springs) and with local weather.
When the actual time of transit is known, tidal heights and streams are calculated and the course to steer worked out to make good the planned track. The OOW must still monitor and adjust, because the stream varies with place and time.
7. Course alterations, wheel over and parallel indexing
7.1 Course alterations and wheel over
On small-scale, large-area charts (open sea, offshore) course alterations usually coincide with the track intersections. In confined waters on large-scale charts, with the margins of safety close, the ship must start turning before the intersection — at the wheel-over position — to settle onto the new track.
A pilot judges the wheel over from experience; ship's officers, lacking that, must derive it from the ship's manoeuvring data and mark it on the chart, choosing suitable visual and radar cues. The best cues for large alterations are Parallel Indexes or visual bearings parallel to the new track; for small alterations a near-beam bearing is often better. The wheel-over position is shown even when the pilot has the con, so the OOW knows it is imminent — part of the officers' monitoring of the pilot.
7.2 Parallel indexing (PI)
Parallel Indexing monitors cross-track tendency in good and poor visibility; the planned PI is marked inconspicuously on the chart at the planning stage. Like any radar technique it should be practised in good visibility before being relied on in thick weather. A radar-conspicuous mark's echo is watched against track lines prepared on a reflection plotter, or against ARPA index lines; it works best North-up, relative-motion, ship-centred.
A fixed target (lighthouse, headland) appears to track past own ship — at the screen centre — on a line parallel and opposite to the ground track. Any cross-track tendency (e.g. a tidal stream) shows up as the target moving off the parallel line. PI can also monitor an event such as a wheel over, marking the target's range and bearing at that point for a distance countdown.
7.3 Waypoints
A waypoint is a charted position where a planned change of status occurs — often a course change, but also: end/beginning of sea passage, change of speed, pilot embarkation point, or anchor stations. Waypoints also serve as reference points for passage time and schedule. Where an electronic navaid stores waypoints, the designators must stay uniform throughout the plan.
8. Aborts and contingencies
No matter how well planned, a passage may have to be abandoned. The plan must prepare for this in advance.
8.1 Aborts and the point of no return
Approaching constrained waters, the ship reaches a position beyond which it can only proceed — the point of no return: water too narrow to turn, or a falling tide and insufficient UKC make retracing impossible. The plan must mark the last position at which the passage can be aborted without the ship being committed, together with a planned track to safe water. The abort point varies with water availability, speed, turning circle and stream direction.
| # | Reason |
|---|---|
| 1 | Deviation from the approach line. |
| 2 | Machinery failure or malfunction. |
| 3 | Instrument failure or malfunction. |
| 4 | Non-availability of tugs or berth. |
| 5 | Dangerous situations ashore or in the harbour. |
| 6 | Sudden weather changes — onset of poor visibility, dangerous increase in wind speed/direction. |
| 7 | Any situation where it is deemed unsafe to proceed. |
8.2 Contingencies
Having passed the abort point and point of no return, the team must still expect events not to go as planned. Contingency plans are made at the planning stage and shown on the chart, so the OOW has instantly available action rather than having to search and plan under pressure.
| # | Item |
|---|---|
| 1 | Alternative routes. |
| 2 | Safe anchorages. |
| 3 | Waiting areas. |
| 4 | Emergency berths. |
Emergency action may take the ship into draught-constrained areas (speed must be reduced) or tidally constrained areas (enter only within the tidal window) — such constraints must be shown clearly.
9. Position fixing and monitoring aids
Many fixing methods exist, but none suits all circumstances. The plan states which method is primary and which are secondary / backup, and how this changes through the passage.
9.1 Primary and secondary fixing
Out of sight of land, GPS may be primary with Loran C secondary. Nearing the coast, GPS stays primary with the radar fix confirming it; eventually the radar fix becomes primary with GPS secondary; in enclosed waters GPS may become inappropriate and fixing relies on radar and visual methods. The rule is to be flexible — but everyone must know which system is in operation.
9.2 Radar-conspicuous objects, visual navaids and lights
To reduce workload, the navigator decides at the planning stage which radar-conspicuous marks and visual aids to use at each stage, and which lights will be seen first at landfall — marked with their maximum visibility range. Floating navaids should be avoided by choice (they may not be on their charted position); when a buoy is used, its position must be confirmed as charted, e.g. by range/bearing from a fixed object or via the local VTS. Highlight Racons and other radar-conspicuous objects; differentiate floating from fixed, and high- from low-powered lights.
9.3 Transits, clearing marks, head marks and clearing bearings
Beyond fixing, simple eye checks confirm the ship is not standing into danger:
| Aid | What it does |
|---|---|
| Transit (Range) | Two identifiable objects in line give a quick position line by eye, no instruments. For best accuracy the observer-to-near-object distance should be no more than 3× the distance between the two objects. Can also cue a pre-arranged action (e.g. wheel over) and check gyro/magnetic compass error. |
| Leading line | A printed transit that is a track line to follow; leads in line = ship on the planned track. |
| Clearing mark | Keeps the ship in a safe area / off a danger — e.g. as long as Rat Island's western end stays open and to the left of Sheep Buoy, the approach is safe to that side of the channel. |
| Head mark | A conspicuous charted object on the projection of the required track; while its compass bearing (corrected, ideally a centre-line repeater) stays constant the ship is on track. The head need not point at it — offset for tide/leeway. A relative bearing is misleading (a ship can circle a target on the same relative bearing). |
| Clearing bearing | A single charted object: while its bearing stays within a stated range (e.g. 028°T – 042°T) the ship is in safe water; shown as NLT 028°T / NMT 042°T (not less / not more than). |
9.4 Range of lights
The maximum range a light can be seen depends on three factors: the combined height of eye and light, the intensity of the light, and the clarity of the atmosphere.
| Range | Definition |
|---|---|
| Geographical range | Depends only on height of light + height of eye; from tables in the List of Lights. Reduced in practice if the light is too low-powered to reach it. |
| Luminous range | Depends on intensity + atmospheric visibility; ignores heights. |
| Nominal range | The range charted beside the light star — the luminous range when meteorological visibility is 10 miles. Not universal: Japan charts the geographical range; Brazil charts the geographical or nominal, whichever is greater. The navigator must know which is shown. ⚠ correção DHN/Miguens: no Brasil cartografa-se o menor alcance |
At the planning stage the navigator compares nominal and geographical ranges and picks the lesser as the range a landfall light should appear (assuming ≥ 10 miles visibility). Only a light whose luminous range exceeds its geographical range can give an approximate fix. Arcs of maximum visibility are drawn on the landfall chart. By the extreme range a powerful light may be seen before radar detects it; a missed light tells the OOW he is not where expected, the light is unlit/obscured, or visibility is poor. The echo sounder, switched on before landfall, likewise warns of approaching danger by a decrease in soundings — though, like a distant light, it is not a fix.
10. Additional information, books and approval
Not essential to safety, but it simplifies execution to mark reminders on the plan so the OOW prepares in time:
| Item | Purpose |
|---|---|
| Reporting points | Reporting to the relevant authority — sometimes compulsory; note the VHF channel and key data, especially for inexperienced officers. |
| Anchor clearance | Positions where anchors must be cleared and anchor stations called. |
| Pilot boarding area | Timely preparation of the pilot ladder and warning to personnel. |
| Tug engagement | Reminder to call the crew to secure tugs. |
| Traffic areas | Where heavy or occasional traffic (ferries, fishing boats) may be met. |
10.1 Fix frequency, regularity and overcrowding
Establish the required fix frequency: a ship close to danger is fixed more often than one in open sea. The guideline is to fix at a period such that the ship cannot get into danger between fixes. If that is impractical (intervals under three minutes are very demanding), an alternative primary method such as Parallel Indexing should be used. Fixes must actually be made at the chosen frequency, not when the OOW feels like it — the only exception being a higher priority such as a course alteration for traffic or an approaching wheel over (fix immediately before the turn and again as soon as possible after).
Where information would overcrowd the working chart or blot out detail, write it well clear of the track (e.g. on the land) and link it with a connecting line or reference letter.
10.2 Planning book, conning notebook
Some information is better in a planning book — times of HW/LW, sunrise/sunset, VHF frequencies — and a ship using a port regularly may keep the whole plan there (or on a computer) for re-use. For long or complex passages an abbreviated edition of the plan goes into a conning notebook, so the conning officer updates himself without leaving the conning position.
10.3 Master's approval, plan changes and AIS
On completion the plan is submitted to the master for approval; all bridge-team members are made aware it is complete and invited to examine and comment. Even the most thorough plan may change during the passage: whoever makes a change must do so with the master's agreement and advise all other members. The carriage requirement for AIS adds information otherwise unobtainable — identifying ships hidden by land or rain and detecting target heading changes early — but, because of manual inputs, its data must be used with care for decisions.
On completion the plan must be submitted to the master for his approval. — Swift & Bailey, Chapter 3 (Master's Approval)
11. Passage planning in one view
Planning converts the appraisal into a chart a tired OOW can read instantly. From shallow water out to traffic room, the chapter reduces to:
| Element | Essence |
|---|---|
| Charts | All charts in order, adjacent and large-scale included, corrected to the latest Notice to Mariners and warnings. |
| No-go areas | Highlight where the ship cannot go; floor = draught + 10%; vary with draught and (in confined waters) with tide/time. |
| Margins of safety / safe water | Buffer the bridge (not just the fix) from no-go; keep depth > draught + 20%; monitorable by clearing bearings or PI. |
| Tracks | Small-scale first then transferred (double-checked) to large-scale; true direction = direction to make good; mark chart change + number; keep distance off danger. |
| UKC / tidal window / streams | Show reduced UKC and the tidal window; pre-correct for stream as the coast nears. |
| Wheel over / PI / waypoints | Mark wheel-over positions with cues (even with a pilot); plan parallel indexes; uniform waypoint designators. |
| Aborts & contingencies | Mark the abort point and point of no return, with a track to safe water; pre-plan alternative routes, anchorages, waiting areas, emergency berths. |
| Fixing & aids | State primary/secondary methods; plan radar/visual marks; transits, clearing marks/bearings, head marks; know which light range is charted. |
| Extras & approval | Reporting points, anchor/pilot/tug reminders; fix frequency & regularity; planning & conning books; master's approval; AIS used with care. |