Module 20 - Special Situations Afloat
Grounding
What you will learn
Build a grounding evidence board before attempting to refloat, and preserve the option to remain supported when moving may worsen flooding or stability.
A grounded yacht may be inconvenient, damaged, unstable or in immediate danger. Tide direction alone does not decide which state exists, so the skipper must inspect people, hull, water, bottom, weather and escape consequences before applying force.
Stop the action that caused the grounding and account for everyone. Fix position, note time, tide height and trend, weather, waves, bottom type, heel and whether the yacht is moving or pounding. Check bilges, tanks, keel area, rudder, steering and machinery spaces without putting crew into an unsafe compartment.
Do not automatically motor hard astern. Propeller and rudder may be exposed to debris or bottom contact, the hull may be supported over a breach, and moving into deeper water can convert limited ingress into uncontrolled flooding. Engine thrust, kedging, heeling and weight transfer each introduce new loads and crew hazards.
A rising tide may increase water under the keel, but it can also increase flood depth, wave action or the consequences of leaving support. A falling tide may allow inspection or make the yacht take the ground, but can increase heel, structural load and isolation. Use the actual height curve, bottom profile, hull form and forecast—not a rising-good/falling-bad slogan.
Choose among remain supported, stabilise, request assistance or attempt a controlled refloat. State the expected benefit, limiting load, crew positions, propeller/rudder clearance, abort signal and where the yacht will go if it moves. After refloating, recheck ingress, steering, propulsion, structure and the safe-haven plan before continuing.
| Evidence gate | Before a refloat attempt | Reason to withhold |
|---|---|---|
| People | Crew counted, protected and briefed | Injury or unsafe deck work |
| Hull and water | Ingress located or bounded and monitored | Unknown or accelerating flooding |
| Underwater gear | Propeller, rudder and keel risk assessed | Likely obstruction or damage |
| Destination | Controlled water and stopping plan | Movement leads into deeper or less protected danger |
| Force | Load, strong point and abort signal defined | Uncontrolled power, kedge or heel load |
Decide whether movement is safer than support
The yacht grounds on a rising tide. Bilge water is above its normal level, but the source is not yet located and deeper water lies astern.
1. Freeze force
Do not use astern power while the damage and propeller/rudder state remain unknown.
2. Build evidence
Monitor water level, inspect accessible structure, confirm tide and assess motion and bottom support.
3. Compare outcomes
Ask whether remaining supported or moving into deeper water creates the lower immediate risk.
4. Set release gates
Attempt movement only with bounded loads, protected crew, an abort signal and a controlled destination.
Sense check: More water under the keel is useful only if the yacht can float without losing flooding, steering or stability control.
Common mistake or limitation
- Treating any rising tide as permission to refloat immediately.
- Using engine power before checking whether the propeller, rudder or a breached hull will be worsened.
- Moving crew or weight without considering heel, deck safety and structural load.
- Refloating successfully but continuing without a second hull, bilge, steering and propulsion check.
Recap
- Grounding response begins with people, position, motion, hull, water, tide, weather and bottom evidence.
- Tide direction changes options but does not decide safety on its own.
- Every refloat method needs bounded loads, protected crew, an abort signal and a controlled destination.
- Refloating starts a new damage assessment; it does not prove the yacht is seaworthy.
Optional quick check
Section 4 of 12
A grounded yacht has unexplained bilge water and deeper water astern on a rising tide. What is the strongest first decision?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying Special Situations Afloat
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