Anchoring, Docking & Mooring Quiz

Re-setting describes an anchor's ability to dig in and hold when the load direction reverses — such as when wind clocks 180 degrees and the rode goes slack before tensioning in the new direction. Good re-setting anchors dig in quickly; poor ones drag while re-orienting.

The Danforth can bury so deeply in soft mud that it becomes impossible to retrieve without diving, and its fluke geometry makes re-setting in a new direction slow and unreliable. As a kedge deployed briefly for a specific purpose, these weaknesses matter less.

The Rocna's roll-bar is a semi-circular bar on top of the shank that causes the anchor to roll to the correct upright orientation when it lands on the seabed, regardless of initial landing position. This prevents the common failure mode of a fluke-up anchor that skates instead of sets.

A 12m boat at the lower end of the 9–12m range could use 15kg; at the upper end (40ft, about 12.2m), 20kg is appropriate. Modern anchor sizing tables favor 15–20kg for this range, and going slightly heavier is prudent for offshore or poor-holding-ground use.

The Delta uses a fixed (non-hinged) shank, which provides more consistent pull geometry and faster, more reliable setting than the CQR's hinged shank. The hinge in the CQR can sometimes allow the fluke to lag behind during setting.

The Rocna, Spade, and Manson Supreme are regarded as the best all-round modern anchor designs — they set fast, hold in diverse bottom types, re-set well, and significantly outperform CQR, Bruce, and Danforth in controlled testing.

The Bruce's claw geometry sits more on the seabed surface than other designs, limiting penetration depth. This makes its holding-to-weight ratio lower than modern concave-fluke anchors. It remains popular as a stern anchor due to its quick deployment.

Manufacturer sizing tables are optimistic — they assume good holding ground and proper scope. Going one size heavier provides meaningful margin for poor conditions, weed, or variable holding ground without significant practical cost.

Chain must be at the anchor end of the rode. This maintains the catenary geometry close to the anchor, keeps the angle of pull horizontal, and provides abrasion resistance on the seabed. Chain at the boat end would hang vertically and provide no catenary benefit.

Minimum depth at HW = tidal range + draft + clearance = 3m + 1.8m + 0.5m = 5.3m. At low water, the depth will be 5.3m − 3m = 2.3m, giving 0.5m clearance under the keel.

When the boat lies beam-on to the wind, the full side profile — hull, deck, rig — is exposed to gusts. This dramatically increases windage loads compared to a head-to-wind orientation. Combined with the snatching from oscillation, rode loads can be very high.

A Bahamian moor — two anchors set 180 degrees apart — restricts swing to the area between the two anchor positions, keeping the boat in a very small footprint. It's used in crowded anchorages or in tidal areas where the boat needs to stay on a specific axis.

The anchor is the spring that holds the bow off the dock while the stern is tied. Deploying it far enough out provides adequate scope so the anchor holds under the loads from wind and other boats, preventing the boat from going alongside and damaging itself.

Minimum HW depth = tidal range + draft + clearance = 2.5m + 1.4m + 0.5m = 4.4m. At low water the depth will be 4.4m − 2.5m = 1.9m, leaving exactly 0.5m under the keel.

Tandem anchoring places two anchors on the same rode, one behind the other, increasing holding in one direction. A V-anchor (or Bahamian moor) deploys two anchors in different directions to restrict swing.

Lazy lines are permanent mooring lines on the seabed in Med berths, with a pickup buoy at the dock face. Instead of anchoring, you pick up the lazy line at the stern and cleat it, which holds the bow off the dock.

A riding sail hoisted on the backstay acts as a weathervane, keeping the bow pointing more reliably into the wind and reducing the oscillating yaw that develops in wind-against-current anchorages.

In a crowded Med moor, anchors from multiple boats overlap. If you wait until others have recovered and moved, your anchor may be trapped under their chains. Standard practice is to motor forward to recover your anchor before or at the same time as neighboring boats depart.

The shank-and-fluke geometry of most anchors requires horizontal pull to drive the fluke deeper into the substrate. Upward-angled pull reduces penetration depth and, at sufficient angle, extracts the anchor. This is why scope — the ratio of rode length to water depth — is so critical.

Vertical distance = depth + freeboard = 4.5m + 1.5m = 6m. Scope 7:1 = 6m × 7 = 42m of rode. Always measure from the bow roller to the seabed, not just water depth.

The catenary (sag) in a heavy chain rode absorbs shock loads — gusts, waves, and sudden boat movement straighten the curve before the load is transmitted to the anchor. This protects both the anchor holding and deck hardware.

'Rk' on a chart indicates a rocky bottom. Rock is poor holding ground — anchors typically can't penetrate it, and if an anchor hooks a crack it may be impossible to retrieve. Seek a nearby sandy or mud bottom instead.

Swing radius = rode length deployed + boat length = 50m + 14m = 64m. Any hazard or other boat within 64m of your anchor could be reached if the boat swings fully.

An anchor holds by digging its fluke into the substrate, using the substrate mass as the holding force. Horizontal pull from the rode drives the fluke deeper. The anchor's own weight contributes very little to holding power.

Vertical distance = depth + freeboard = 8m + 2m = 10m. 7:1 scope = 10m × 7 = 70m of rode.

Firm sand is the best holding ground — anchors penetrate easily, set quickly, and resist horizontal pull well. Rock is typically the worst, as anchors can't penetrate it and may be impossible to recover if hooked.

Fixed bearings to charted objects ashore provide a reference. If the bearings change significantly over time, the boat has moved — indicating the anchor is dragging. This is the simplest and most reliable drag detection method.

The catenary — the sag curve formed by the chain's own weight — absorbs shock loads by straightening under sudden load before the tension reaches the anchor. Rope is too light to form significant catenary and transmits shock more directly.

The pivot point is approximately 1/3 from the bow. This means the stern swings through a much wider arc than the bow when turning at slow speed — a critical consideration when maneuvering in tight marina spaces.

Wind pushing toward the dock is an ally. You need less throttle, can approach more gently, and have more time to get lines on. The wind helps complete the docking. Approaching aggressively into downwind-assisted docking typically means hitting the dock hard.

With the forward spring holding the bow, turning the helm toward the dock and advancing throttle uses the spring as a pivot point — the stern swings away from the dock. Once the stern is clear, cast off the spring and motor forward. This works against wind or current holding you on the dock.

A right-hand prop in reverse walks the stern to port. When coming alongside port-side-to, this walk assists the final swing of the stern toward the dock. Starboard-side-to requires fighting the prop walk to prevent the stern from kicking away from the dock.

With the pivot point 1/3 from the bow, the bow has a short moment arm and moves through a small arc. The stern has a long moment arm (2/3 of the boat length) and swings through a much larger arc. This is why the stern can swing into a piling while the bow is still feet away.

A forward spring (bow end secured to dock, line running aft) creates a pivot point at the bow. Helm toward dock and forward throttle causes the stern to kick away from the dock while the bow stays against the spring — allowing departure bow-first from a tight berth.

A right-hand propeller in reverse walks (kicks) the stern to port. This is the paddlewheel effect — the lower blade meets denser water than the upper blade, producing a net sideways force. Experienced sailors use this to assist port-side-to dockings.

If the approach is compromised — lines dropped, boat out of position, unexpected obstacles — the correct response is to abort immediately with forward gear and exit. Trying to salvage a compromised approach from inside a slip is how topsides get damaged.

Crew briefing — who handles which line, who steps ashore, what 'abort' means and looks like — is the most important preparatory step. Fenders and line preparation are essential too, but without a clear plan and role assignment, those preparations may not be executed correctly under pressure.

The goal is to arrive at the dock precisely when the boat's forward momentum has expired — dead in the water at the target position. Too much speed means hitting; too little means stalling before reaching the dock and losing control.

A backed jib — sheeted to windward so the clew is pulled to the windward side — pushes the bow downwind and acts as a brake. The sail area is still generating force, but in a direction that both turns and slows the boat. It's used as a last-resort stop or to check excessive headway.

On a downwind approach, heading up to slow the boat would turn it away from the dock — the boat accelerates rather than decelerates if the heading changes toward the wind. There is no reliable way to brake a downwind approach in real wind; the boat arrives fast.

Setting an anchor requires a controlled reverse load to drive the fluke into the seabed. Wind or current can provide some backward drift, but it is uncontrolled and rarely as forceful as engine reverse. In poor holding ground especially, a sail-set anchor may not be properly embedded.

Luffing — steering toward the wind — causes the sails to start flapping (luffing) as the angle between the sail and the wind decreases. Drive drops and the boat slows. This is the fundamental speed-control mechanism in a windward docking approach.

If the approach is too fast or misaligned, bear away and circle for another attempt. Grabbing the buoy while at speed can injure crew and damage the bow. Dropping the anchor is not a practical emergency stop. The second attempt is the seamanlike choice.

A downwind approach in 15 knots of true wind is hazardous — the boat will be moving fast and there is no way to slow it by heading up. The seamanlike response is to find a different approach angle or use the engine (or anchor and wait for conditions to change).

A dummy approach (sailing past the target on the planned heading at speed) lets you observe how the boat behaves on that heading, measure the current effect, check for obstructions, and calibrate speed and distance for the real approach — all before committing.

Sailing under a single sail (jib only or main only) gives more control — one sail is easier to luff, ease, back, or lower quickly than two. Full sail in a confined docking approach leaves less margin for speed adjustment.

Nylon's 10–15% elongation is the critical property for dock lines. This stretch absorbs surge, peak loads from gusts and wake, and prevents shock transmission to deck fittings. Polyester is too stiff and would transmit full shock loads to hardware.

A fully compressed fender that flattens against the hull means it has used its full range of deformation. Any further surge force will bring the hull into contact with the dock through the bottomed-out fender. Size up to a fender that doesn't fully compress under typical load.

At a fixed dock in a tidal area, as the boat rises the dock lines become shorter (relative to the boat-to-dock distance). Short lines at steep angles will lift the boat against the dock or snap. Long lines rigged at low horizontal angles accommodate the tidal movement.

Passing your eye up through existing eyes (daisy-chaining) means your line can be removed without disturbing other boats' lines, and vice versa. Adding your eye directly on top traps the lines below — other boats cannot leave without removing your line first.

Nylon stretches significantly under load, acting as a buffer between the boat's inertia (during a surge) and the dock hardware. Polyester is too stiff — it transmits full shock loads to cleats and dock fittings, which can fail or pull out.

Spring lines running at a low angle along the dock need to be long enough to run from the boat's bow or stern to a dock cleat that is behind or ahead of the boat respectively. 1.5× the boat's length is a practical guide for a useful spring length.

In a large tidal range, the boat drops with the water while the fixed dock stays at the same height. Short lines go taut as the geometry changes. The solution is longer lines rigged at low angles, which can accommodate the full tidal movement without going taut.

One locking hitch is correct and sufficient. Additional hitches make the cleat hitch extremely difficult to release under load — a serious problem if you need to let go the line quickly in an emergency (medical incident, fire, departure under threat).

The daisy chain technique — passing your eye up through existing eyes from below — allows any boat to remove their line independently. Placing your eye on top traps all lines below and prevents other boats from leaving without your permission.

Private moorings are typically set for the owner's specific boat size and weight. A mooring rated for a 5-ton boat may fail if a 12-ton boat loads it in a storm. Always verify the mooring's rated capacity before using it for an overnight stay.

The mooring pennant should lead through the bow roller (to prevent chafe) and be cleated to both bow cleats or to the samson post. Spreading the load across two cleats reduces the chance of a cleat pulling out in heavy conditions.

Pitting and significant rust on a riser chain indicate corrosion that weakens the links. A corroded chain can fail at loads far below its rated strength. The prudent response is to back up with an anchor or find a better mooring — particularly before an overnight stay.

The boat sails back and forth on the mooring throughout the night as wind direction varies. The pennant rubs on the bow roller during this motion — hours of continuous abrasion on an unprotected nylon pennant can wear through it by morning.

Always approach a mooring into the wind or dominant current. This allows you to use forward throttle to control approach speed and to stop the boat naturally as the bow reaches the buoy. A downwind approach is too fast and cannot be controlled with engine power alone.

As the boat moves around the mooring overnight, the pennant rubs continuously on the bow roller. Without chafe protection, a nylon pennant can wear through in a single windy night. A leather sleeve, rubber guard, or chain pennant prevents this.

Pitting and rust on a riser chain are signs of significant corrosion that reduces the chain's actual strength well below its rated capacity. A corroded riser can fail in a storm load. Deploying an anchor as backup, or finding a better mooring, is the correct response before an overnight stay.

If you miss the buoy, circle and approach again from upwind. Reversing toward the buoy risks fouling the pickup line or pennant around the propeller. A clean second approach is always the right call.

Visitor moorings are managed by a harbor authority, inspected on a schedule, and designed for a range of visiting boat sizes. Private moorings are set by individual owners for their specific boat — maintenance standards are unknown and the mooring may not be rated for your boat's weight.

At anchor, a boat weathercocks — it will swing to whichever force (wind or current) is stronger. Head into the stronger force on approach so the boat is aligned as it will lie once anchored. In tidal waters, current is usually stronger than wind up to about 15 knots.

If chain piles up under the bow, it falls on top of the anchor as it hits the seabed. When you apply reverse load, the chain tightens over the anchor rather than pulling the shank horizontally, preventing the fluke from setting correctly.

A snubber transfers the anchor load from the inelastic chain to a stretchy nylon line, absorbing shock loads from waves and gusts before they reach the windlass and bow hardware. It also reduces noise and prevents chain chafe on the bow roller.

Windlasses are designed to lift the anchor vertically, not to drag the boat horizontally against chain tension. Motoring forward keeps the chain nearly vertical, reducing the load to a manageable lift rather than a horizontal haul that could overload or damage the windlass.

A set anchor holds the bow in a fixed direction and prevents the boat from moving astern under reverse power. The bow 'locks up' — it stops swinging and holds steady. If the boat continues moving astern or the bow swings, the anchor is not set.

Lower the anchor under control, then pay out rode gradually as the boat falls back, keeping the rode in a gentle curve. Reach full calculated scope before applying reverse load to set. Dropping all the chain at once piles it on top of the anchor.

A trip line is attached to the anchor crown and used to invert the anchor when it fouls. Pulling on the trip line reverses the load direction, lifting the fluke from whatever it has hooked, allowing recovery when normal lifting fails.

A steady, continuous change in bearing to a fixed reference object indicates the boat is moving relative to the seabed — the anchor is dragging. Oscillating changes might indicate swinging; a one-directional trend indicates drag.

Windlass struggle indicates the chain is under horizontal tension — the boat is being dragged toward the anchor rather than positioned above it. Motoring forward reduces the angle and load to a vertical lift the windlass can handle.