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Trim Playbook — Lupo Di Mare

Trim (Mainsheet / Headsail / Kite Trim) role. Watch system, squall protocol, and safety basics are in Crew Orientation.

TL;DR

  • Trimmer is the driver's coach — call pressure, sheet load, and boat balance continuously.
  • Hold the working sail at target through small lulls. Only call for change when conditions move outside the briefed window.
  • Sheet pressure runs the peel — old sheet stays loaded until new sail bears load. Premature ease costs 0.5+ kts.
  • Lead position set on every sail change — before the "trimmed" callout, not after.
  • Trim feels the shift first. Flag persistent wind trends to Watch Captain before instruments catch up.
  • Heavy air: never luff the main — ease mainsheet to depower; vang on hard; traveler to leeward.

Trim Mode Quick-Ref

Mode Use when Sheet pressure Twist Lead
Pointing Building breeze upwind; need height High (max acceptable) Tight (close leech) Forward
VMG Standard upwind cruise Target per polars Balanced Per sail
Reaching (high) TWA 60–80°, target speed Eased ~10° from pointing More open Aft 1–2 holes
Reaching (broad) TWA 90–130°, reaching kite Loaded but free Open Aft
Running TWA 130°+, A-sail or SS Variable per gust Maximum twist Furthest aft
Heavy air ease Overpowered, any TWA Ease before luffing Vang-controlled —

Mode change is announced to Driver: "going high" / "going low" / "VMG mode now."

Crew Weight & Boat Balance

Movable crew weight is a trim control like sheet or lead. Two rules dominate offshore; then bias fore/aft by mode.

Standing rules (always true):

  • Keep the ends light. Off-watch bodies and loose gear out of the bow and stern. Weight in the ends increases pitching, and pitching through Gulf Stream chop is the #1 upwind speed loss. Off-watch sit/sleep amidships during racing, not the forepeak.
  • Low and to the rail in breeze. Weight to windward for righting moment; weight low for stability.

Fore/aft by mode:

Mode Crew weight Why
Upwind, light air Forward + to leeward Immerse the fine bow entry, lift the transom, cut wetted-surface/transom drag
Upwind, breeze + chop Aft + windward rail Stop the bow burying/pounding; control heel
Reaching / running, breeze Aft Lift the bow, prevent nosedive/broach, help her plane
Running, light air Forward Pull the transom clear, reduce drag

Lupo-specific (rule of thumb — confirm with skipper, calibrate on the water): the 12.98's fine bow entry and beamy, flat aft sections make her sensitive to bow trim. Default offshore is weight centered and low; move forward only as a light-air trim — don't bury the bow.

Trim calls the shift to Driver and Watch Captain like any mode change: "crew aft" / "crew forward" / "weight up." Frozen gear stowage (the packing decision) is in Boat Specs → Stowage & Weight Distribution.

Watch-On Duties

  • Inspect sheet runs at handoff: jib leads, kite sheets, mainsheet purchase, traveler car, vang, cunningham.
  • Verify working sail trimmed to current target per polars (02_polars/lupo_polar_analysis.md) or Navigator's last call.
  • Track instrument trend (TWS, TWA, BSP, VMG) — feed Driver and Watch Captain a continuous read.
  • Pre-stage next sheet/lead configuration for forecast wind shift or sail change.
  • Call sheet pressure to Driver every few minutes: "loaded," "eased," "on the limit."
  • Listen for Bow and Pit callouts during peels; adjust sheet pressure accordingly.

Watch-Off Duties

  • Brief incoming trimmer on current target mode (pointing vs VMG), trim trend, any sail-shape concerns.
  • Note chafe on sheets, blocks, or leads in the watch log.
  • Sleep to stay mentally fresh — Trim is a cognitive role as much as a physical one.
  • Off-watch is on-call for any maneuver requiring four hands on sheets.

Sail Change Choreography

Trim's key rule: hold the old sheet at trim until you SEE the new sail bearing load — not when Pit says "halyard tight." Rate of old sheet ease determines whether the peel costs 0.2 kts or 0.8 kts.

Per-maneuver trim detail

J-sail peel:

  1. Pre-stage new jib sheet leads if different from current (car positions per sail — see Race-week deliverables).
  2. Do NOT ease old sheet until new sail bears load.
  3. Ease old sheet at rate matched to Bow's drop pace.
  4. Once old sail is at deck, sheet new sail in smoothly to target trim.
  5. Verify lead position and twist; adjust within target range.
  6. Confirm "trimmed" to Watch Captain.

Asymmetric set:

  1. Pre-set sheet leads (turning blocks, twings if used) before set call.
  2. On Bow's "ready to hoist," take slack out of working sheet so kite fills cleanly at masthead.
  3. As kite reaches masthead, sheet in immediately — do not allow kite to flog at full hoist.
  4. Driver and Trim coordinate: Driver bears off to working angle as Trim sheets in.

Asymmetric peel (A→A):

  1. Bring new sheet to load as new kite fills; ease old sheet as old kite collapses.
  2. Maintain boatspeed — Trim is the variable that determines peel cost.

Spinnaker douse:

  1. Coordinate with Pit and Bow: "ease on three."
  2. Ease working sheet as halyard comes down — kite must collapse to leeward shrouds or down companionway.
  3. Keep tension on lazy sheet so foot is controllable for Bow.
  4. Return to working headsail trim immediately after kite contained.

Code 67 deploy/recover:

  • Deploy: sheet in progressively as Pit unfurls; boat accelerates continuously.
  • Recover: ease sheet to depower; Pit takes strain on furl line; ease to zero as sail furls.

Reef in:

  1. Ease mainsheet on Pit's call; ease vang.
  2. Once Pit has tack cringle hooked and reefing line tensioned, return to mainsheet trim for reefed configuration.
  3. Re-tension cunningham and re-trim. Working sheet load increases slightly with smaller sail plan.

Comms Protocol

Trim calls in: - Continuous pressure reads to Driver: "loaded," "eased," "on the limit," "high mode now," "VMG mode now." - "Sheet ready" — pre-rig confirmation for next sail. - "Trimmed" — completion callout after any sail change. - "Going hot" / "going down" — TWA mode change advisory to Driver. - "Sheet hung up" — stops the maneuver immediately.

Trim calls out: - To Driver: target angle, target boatspeed, mode, pressure feel. - To Bow: sheet ready or not ready for set, douse, peel. - To Pit: load confirmation so Pit knows when to release/secure halyards. - To Watch Captain: any persistent wind trend instruments haven't caught yet.

Escalation: - Sheet chafe approaching failure, broken sheet, blown lead block → immediate call to Watch Captain. - TWS trend pushing outside current sail's range → advisory to Watch Captain.

Failure Modes

# Mode Symptom Recovery Prevention
1 Easing old sheet before new sail loaded Boat slows 0.5+ kts mid-peel Re-sheet old sail momentarily; then transition Hold old sheet until you SEE new sail bearing load
2 Over-sheeting kite at hoist Kite never fills; boat slow off the set Ease to refill; reset trim Progressive sheet-in matched to Driver's bear-away
3 Wrong lead position for wind angle Top tell-tales stalled or always flying; BSP off target Adjust lead car forward (close leech) or aft (open leech) Lead set before "trimmed" callout, not as afterthought

Race-Week Deliverables

Item Owner Target
Jib lead car positions per sail (J1/J2/J3/J4) Skipper + Trim T-7 brief — document in race-week trim notes
Cross-references

Onboard cards: - Card 01 — Start to Block Island - Card 04 — Gulf Stream Entry — Stream chop shifts trim mode toward reaching with boat-balance priority - Card 07 — Mid-Ocean Transition — trim mode shifts as wind angle evolves - Card 10 — Tactical Scenarios — Heavy Air section

Reference: - 02_polars/lupo_polar_analysis.md — target BSP and TWA per TWS - 03_sail_crossovers/crossover_notes.md — when to change sail vs trim through it - sail_inventory.md — sheet leads, blocks, and sail-specific configurations