Day nineteen. Your second stew has averaged five broken hours of sleep a night for a fortnight. This morning she signed the rest-hours record showing ten hours, because that is what the form needed to say. Tonight she will handle a hot service, chemical stores and a guest with a medical condition. Everyone thinks she is coping, including her.
What fatigue actually does
Fatigue is not tiredness; it is a measurable degradation of performance. It attacks precisely the abilities leadership depends on:
| Function | Effect of fatigue |
|---|---|
| Vigilance and attention | Misses cues, fixates on one task |
| Short-term memory | Forgets steps, loses the plan |
| Risk perception | Accepts risks that would normally be refused |
| Decision-making | Chooses the first option, not the best |
| Mood and teamwork | Irritability, withdrawal, silence when challenge is needed |
| Self-assessment | The fatigued person reliably rates their own performance as fine |
That last line is the dangerous one. Fatigue removes the very faculty you would use to detect fatigue, which is why it must be managed by the system and the HOD, not by the individual.
The interior fatigue profile
Interior crew carry a distinctive pattern: early starts and late finishes with a long low-activity gap in the middle, noise and vibration in crew cabins, a shared bunk space, night turndowns, and back-to-back charters with no real recovery. Add dehydration, heat, alcohol at crew dinners and long-haul travel between yards, and impairment compounds.
Rest hours
Minimum hours of rest are set under STCW and the Maritime Labour Convention and are implemented through your flag state, your Seafarer Employment Agreement and the yacht SMS. The principle to hold onto is simple:
- Rest hours are a safety limit, not a target to be negotiated around.
- Records must be accurate. A falsified record is a serious matter that removes the yacht ability to see a real problem.
- The exact figures, exceptions and any permitted exemptions are for your SMS, your flag state and the Master to confirm. Do not rely on memory or on what the last boat did.
What a HOD actually does about it
- Design the rota to protect a genuine, uninterrupted block of sleep, not fragments.
- Rotate the worst duties. Do not let the same stew take every late turndown.
- Watch for the signs described above and remove the person from safety-critical or guest-critical work.
- Escalate honestly: "The current programme cannot be run within rest hours with three interior crew." That is the Master problem to solve, and they cannot solve what they cannot see.
Onboard Notes
- Never ask, hint, or allow a crew member to record rest they did not take. You will meet this pressure; refusing it is the job.
- A fatigued crew member who says they are fine is not evidence that they are fine.
- Fatigue explains error; it does not excuse the failure to manage it. Manage the rota before you have to explain the incident.