Fatigue and Weather at the End of a Field Campaign
It is day 12 of a 14-day nearshore survey. The crew has worked 11-hour days with one rest day. The forecast shows 20-knot winds and 1.5 m seas building to 25 knots and 2 m by afternoon. Your vessel is a 12 m survey launch with a multibeam system and a single operator who is also the coxswain. Two lines remain to complete coverage of a 3 km stretch, and the tide window for shallow-water coverage closes tomorrow. The operator reports feeling tired but willing to continue. The client wants the campaign finished on schedule.
1. What factors determine whether to continue or stand down, and what is your decision?
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Factors:
- Fatigue: 11-hour days over 12 days with one rest day is a cumulative fatigue risk. A single operator/coxswain has no redundancy; fatigue impairs judgement, reaction time, and data quality.
- Weather: 20–25 knots and 1.5–2 m seas in a 12 m launch are marginal to unsafe for precise multibeam work; motion will degrade data and increase risk of injury or equipment damage.
- Tide window: The shallow-water window closing is a schedule pressure, not a safety justification.
- Regulatory/operational: Many operators have fatigue-management policies and sea-state limits; check them.
Decision: Stand down for the afternoon. The combination of fatigue, marginal sea state, and single-operator redundancy is a clear stop-work trigger. Safety and data quality outweigh schedule.
2. How do you manage the schedule and the client relationship after standing down?
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Schedule management:
- Re-plan the remaining two lines for the next suitable weather/tide window, possibly with a shorter workday and a rested operator.
- Consider whether the shallow-water window can be met with a reduced scope or a different vessel; if not, communicate the revised completion date early.
- Document the weather forecast, sea state, and fatigue assessment as the basis for the decision.
Client relationship:
- Notify the client promptly with the reason (safety and data quality), the revised plan, and the expected impact.
- Emphasise that proceeding would risk both personnel safety and non-compliant data, which would cost more in re-work.
- Offer interim deliverables (processed lines completed so far) to maintain momentum.
A transparent, documented decision protects both the crew and the project.