Why plans fail without thinking — and why compliance alone is not safety
Contents
Use the links below to jump to any section:
- What Passage Planning Really Is
- Why A→P→E→M Exists
- Appraisal: Thinking Before Drawing
- Planning: Turning Risk into Structure
- Execution: Where Most Plans Quietly Fail
- Monitoring: The Most Neglected Phase
- Why “We Had a Passage Plan” Is Not a Defence
- Common A→P→E→M Failures Seen in Accidents
- Turning A→P→E→M into a Continuous Loop
- The Professional Passage Planning Mindset
1. What Passage Planning Really Is
Passage planning is often misunderstood as a document: a printed chart, an ECDIS route, a checklist signed before departure.
In reality, passage planning is a thinking process.
The plan is only the visible output of that process. When the thinking is weak, the plan may still look neat, approved, and compliant — but it will not protect the ship.
A good passage plan does not guarantee safety.
A bad passage plan guarantees surprise.
2. Why A→P→E→M Exists
A→P→E→M stands for:
- Appraisal
- Planning
- Execution
- Monitoring
It exists because navigation is not static.
Ships move through changing environments, with changing crews, changing weather, and changing risks. A linear “plan once and follow” mindset fails in the real world.
A→P→E→M forces navigation to be iterative, not ceremonial.
3. Appraisal: Thinking Before Drawing
Appraisal is the most important stage — and the most rushed.
This is where the navigator asks:
- What information do I actually have?
- What do I not know?
- Where are the real risks?
- What can go wrong here?
Appraisal includes charts, publications, weather, tides, traffic, vessel limitations, and human factors.
If appraisal is weak, planning becomes decorative.
Lines drawn without understanding simply move risk around the chart.
4. Planning: Turning Risk into Structure
Planning is where information becomes geometry.
This is where you decide:
- where the ship will go
- where it must not go
- how close is too close
- what margins are acceptable
Planning includes more than route lines. It includes no-go areas, safety depths, XTE limits, speed strategies, abort points, and contingency thinking.
A professional plan is not tight and elegant.
It is forgiving.
If a plan requires perfection to remain safe, it is already unsafe.
5. Execution: Where Most Plans Quietly Fail
Execution is the transition from paper to reality.
This is where many plans die — not dramatically, but quietly.
Typical execution failures include:
- speed changes that were never considered
- shortcuts taken to “save time”
- assumptions that conditions will remain as planned
- plan details that were never briefed properly
A plan that exists only in the navigator’s head does not survive watch changes.
Execution requires shared understanding, not silent expectation.
6. Monitoring: The Most Neglected Phase
Monitoring is the phase that keeps A→P→E→M alive.
It answers one question continuously:
“Is the ship still operating within the plan’s assumptions and limits?”
Monitoring is not just position fixing. It includes:
- checking margins
- watching trends
- detecting plan erosion
- recognising when the environment is changing
Many accidents occur not because the plan was wrong, but because no one noticed it had stopped being valid.
7. Why “We Had a Passage Plan” Is Not a Defence
In accident investigations, the phrase “a passage plan was available” appears frequently.
It rarely helps.
Investigators look for evidence that the plan was:
- understood
- used
- monitored
- challenged when reality changed
A plan that exists but is not actively used offers no protection — legally or practically.
Compliance is not competence.
8. Common A→P→E→M Failures Seen in Accidents
Across groundings and collisions, the same breakdowns appear repeatedly.
Appraisal fails when risks are underestimated.
Planning fails when margins are too tight.
Execution fails when pressure overrides discipline.
Monitoring fails when expectation replaces observation.
Rarely do all four fail at once.
One weak link is enough.
9. Turning A→P→E→M into a Continuous Loop
A→P→E→M is not a checklist to complete once.
It is a loop.
When conditions change, appraisal must be revisited.
When assumptions change, planning must be adjusted.
When execution drifts, monitoring must intervene.
Professional navigation means being willing to re-plan, not just press on.
10. The Professional Passage Planning Mindset
Professional passage planning accepts one uncomfortable truth:
The plan will be wrong — the question is when, not if.
The role of A→P→E→M is not to prevent error.
It is to detect it early, manage it calmly, and prevent it becoming irreversible.
A good navigator does not follow the plan blindly.
They manage deviation intelligently.
Closing Perspective
A→P→E→M is not bureaucracy.
It is structured thinking under uncertainty.
Ships do not get into trouble because they had no plan.
They get into trouble because they stopped thinking once the plan was made.
Tags
passage planning · APEM · bridge navigation · voyage planning · maritime safety · bridge watchkeeping