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ONBOARD CARD 07 — Mid-Ocean Transition Zone

Phase: Post-Stream south wall to ~200 nm from Bermuda (approximately 31–35°N). Typical elapsed time: Race start +48–65 h

TL;DR

  • Fatigue is now a first-order tactical input — sail-change cost may exceed gain.
  • Resist over-management. VMG consistency beats constant intervention.
  • Navigator needs uninterrupted time at the chart table.
  • Rest windows > small speed opportunities. Final 200 nm needs alert crew.
  • Skip sail changes <0.2 kts gain or <2 h sustained.
  • Wake Navigator on persistent unexpected current; Skipper on wind <5 kts >3 h with fleet catching.

DATA TO CHECK

Every 4–6 hours: - GPS/log current vector: any persistent set in unexpected direction (warm eddy signature)? - Wind trend: fading, stable, building? Compare to pre-race forecast. - Boat speed vs polar target: significantly below → check for adverse current.

Key question: is the "Bermuda parking lot" starting to develop? - Wind <8 kts and fading with no forecast improvement in 12 h: likely yes. Accept it; do not burn crew.

TRIM / SAIL

Conditions Sail
12–20 kts reaching Code 67 / A3
8–12 kts light reaching Code 67 or A1-1
20–28 kts reaching A3
6–10 kts, S or SE wind J1 / Code 67
<6 kts, drifting A1-1 or J1, patience

If a sail change is worth less than 0.2 kts for less than 2 hours, skip it and rest the crew.

FATIGUE MANAGEMENT

Day 3. Crew has not slept fully on a boat they are still learning. Fatigue affects decision quality, sail change execution, and safety.

Watch rotation: - Maintain strict rotation; do not pull crew off rest for marginal opportunities. - Avoid all-hands evolutions unless maneuver is clearly worth >0.3 kts sustained. - If a watch is depleted and no urgent tactical need: let off-watch sleep longer.

Skip vs pursue: - Skip: peel between asymmetrics for <0.2 kts; sail change in deteriorating conditions with unclear gain. - Pursue: meaningful wind shift requiring gybe for >1 kt VMG gain; WCE detour Navigator confirms saves >2 h.

Signs of crew fatigue affecting performance: - Slow or hesitant responses to sail trim calls - Repeated questions about what we're doing and why - Unnecessary deck congregation at the helm - If you see these: simplify sail plan, reduce maneuver frequency, protect rest.

TACTICAL PATIENCE

Every hour brings you closer to a result largely set by the first 48 hours of racing:

  1. Hold the plan. Unless Navigator identifies a meaningful change in wind or current, the routing plan from race start is still the plan.
  2. Don't chase. Boats visible on AIS may be different classes with different corrected-time implications. Do not abandon routing to chase visible traffic.
  3. One major decision per watch. Limit course/sail changes to once per watch rotation unless a clear opportunity or threat demands otherwise.
  4. Commit. Once a decision is made, sail it fast. Re-litigating with tired crew is corrosive.