Module 7 - Charts & Publications

Advanced Scenario Check: Release the Route

What you will learn

Combine chart status, TSS and firing-area information, local directions and a timed entrance gate into one conservative release decision and crew brief.

A route can fail even when each source looks individually plausible. The Yachtmaster task is to connect current information to the passage decision, preserve the fallback and state exactly what would reopen the route.

At 2015 a fictional yacht is preparing to cross a charted traffic separation scheme and pass a firing-practice area before entering a harbour. The relevant chart is current only after its outstanding notices are resolved; a current warning may alter firing activity; Sailing Directions and the harbour's local notice describe the entrance; and the digital route shares one chart service and GNSS path across two displays.

The nominal harbour entrance ETA is 2145. A credible twenty-five-minute delay for traffic and tide produces 2210. The local direction in this fictional scenario closes the entrance at 2200. The optimistic ETA passes the gate, but the monitored case does not. The route therefore cannot be released on the nominal time alone.

Do not solve this by choosing the newest-looking source. The chart establishes routeing, dangers, notes and cautions; current NMs and T&P information update maintained products; navigational warnings may carry urgent activity; Sailing Directions and local notices add operational detail; tides and weather change timing and margin. Each has a different function, coverage and update path.

At 2015, preserve the hold or diversion while it remains straightforward. Assign one person to vessel and traffic control and another to resolve the information gaps and recalculate the gate. Reopen the route only if the chart/publication set is current, the warning and local-direction conditions are satisfied and a realistic monitored ETA retains the chosen margin.

This written scenario is not a live TSS, firing-range or harbour instruction. Real decisions require the applicable COLREGs, charted routeing, warnings, harbour directions, vessel, traffic, tide, weather, visibility, crew and skipper judgement.

Worked example

Test the nominal 2145 entrance ETA against a credible twenty-five-minute delay and the fictional 2200 closure.

1Nominal margin: 2200 − 2145 = 15 minutes.
2Monitored delay case: 2145 + 25 minutes = 2210.
3Gate result: 2210 is 10 minutes after the 2200 closure, so the monitored case fails before any extra contingency allowance.
4The unresolved firing warning and chart-update chain are separate release failures; a passing time calculation would not cure them.
5Keep the hold or diversion open, resolve the information set and build a new plan rather than defending the original nominal ETA.

Sense check: A fifteen-minute nominal margin cannot absorb a credible twenty-five-minute delay. Calling 2145 the ‘planned ETA’ does not make the 2200 gate safe.

Advanced Scenario Check: Release the Route
Information source	Question it answers	Failure in this scenario
Chart, notes and routeing	Where are the scheme, dangers, limits and cautions?	Outstanding amendments prevent a current release record
Warnings and firing information	What urgent or time-limited activity changes the route now?	The current firing status is unresolved
Sailing Directions and local notice	What operational entrance detail and local direction applies?	The fictional 2200 closure is a hard gate
Tide, traffic and weather	What changes ETA, sea room and operating margin?	A credible 25-minute delay moves arrival to 2210
Fallback	Where can the yacht wait or divert before the route is forced?	It must be used while still controllable

Brief facts, gaps, decision and reopening trigger

The crew ask whether the yacht can depart while the navigator checks the outstanding notice and firing warning underway.

1. Facts
State the accepted 2015 time, nominal 2145 ETA, fictional 2200 closure, chart and publication products and the shared digital dependencies.
2. Gaps
Name the unresolved chart notices, current firing warning, harbour direction and realistic traffic/tide timing rather than saying ‘some updates are missing’.
3. Decision
Keep the route closed and use the briefed hold, delay or diversion while the information and timing remain controllable.
4. Reopening trigger
Require a current coherent information set and a monitored entrance ETA that protects the chosen margin before release.

Sense check: A crew member should be able to repeat which route is closed, why, where the yacht will wait and what exact evidence can reopen the decision.

Common mistake or limitation

Treating the nominal ETA as the decision while ignoring a credible delay case and the operational gate.
Assuming a chart correction will incorporate every current warning, local direction, tide, weather or traffic condition.
Checking the unresolved information underway after departure has consumed the simplest hold or diversion option.
Describing the problem in technical detail without giving the crew a closed route, safe action and reopening trigger.

Recap

Match each operational question to the source that can answer it.
Test gates against a realistic monitored case, not only the nominal plan.
Keep independent information failures separate; one resolved source does not clear the others.
Brief the safe action and exact reopening trigger before the fallback is forced.

Optional quick check

Section 10 of 10

A nominal 2145 entrance ETA precedes a fictional 2200 closure, but a credible 25-minute delay gives 2210 and the current firing warning is unresolved. What is the defensible release decision?

Sources and factual review

Reviewed 20 August 2026 - Compass Revision editorial review.

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