Remember to check keels and rudders
Published on May 27th, 2023
by Sally Lindsay Honey, Chair, World Sailing Special Regulations Sub-committee
At least 93 keels have been lost in the last four decades with 29 lives lost as a direct result. Rudder loss, though not usually as immediately life-threatening, often causes serious hardship for those aboard as well as significant cost and danger for vessels required to assist.
You can reduce the likelihood of either emergency by addressing potential problems before they develop. At every haul out, especially after a grounding or hitting underwater obstacles, have a qualified person inspect the keel and rudder both internally and externally while the boat hangs in the slings.
Check for keel movement, requirements for tightening keel bolts, keel bolt placement issues (a single line may cause repeated bending stress), cracks around rudder post bearing(s), and unusual areas staying wet that may indicate moisture in the laminate. Inspect for these issues frequently.
World Sailing’s Offshore Special Regulations now require effective Cat 0-2 race boat owners to have a qualified person inspect their keel and rudder at least every two years and after significant groundings.
The definition of a “qualified person” varies from “a designer, builder or marine surveyor” to an experienced boatyard boss where the boat is hauled. For Mo3 level inspections, the owner or the owner’s representative may do the inspection. If you have an integral keel, inspect it for moisture retention and possible laminate issues.
Even for those not bound by the OSRs, it is good seamanship to periodically inspect your keel and rudder. A brief review of the OSR 3.02 requirement and Appendix L follows:
• Mo0,1,2: 3.02.2 Effective 1 January 2022: Structural Inspection – Consult the owner’s manual for any instructions for keel bolt checking and re-tightening. The inspection is to be conducted by a qualified person with the boat out of the water. Check externally that there are no visible stress cracks particularly around the keel, hull/keel attachment, hull appendages and other stress points. Inside the hull, check backing plates, bolting arrangements and keel floors.
• Mo0,1,2: 3.02.3 Effective 1 January 2022: Evidence of a structural inspection in accordance with 3.02.2 within 24 months before the start of the race or after a grounding whichever is later.
Appendix L – Model Keel and Rudder Inspection Procedure – Main points (see OSRs for details):
• Inspection shall be completed by “a qualified person” both internally and externally (out of water). It is the responsibility of the owner to undertake any repairs.
• Consult Owners’ Manual for the specific boat, steering system and type of keel. Inspect high-load areas, pay attention to prior repairs.
• Internally, check backing plates, bolting arrangements, sump area and keel floors for any signs of cracking, weakening, or de-laminated tabbing; tighten bolts, inspect for crevice corrosion, “ovaling” of bolt holes, de-bonding of support structure.
• Externally, check for stress cracks or movement at keel/hull interface, keel tip deflection, high stress areas at forward/aft hull attachment areas, large deep blisters, which can indicate separation.
• Rudder/Steering system – check for steering line chafe, bearing area damage/cracks, shaft & blade integrity, tip deflection, corrosion or cracking of rudder straps and gudgeons, if applicable.
• Lifting and swing keels: ensure no significant stress cracks in structure around pins supporting the keel or extensive corrosion on pins, cylinders and supporting metal structure.
• There is a form included in Appendix L to record the inspection.
Even if this inspection is not required in your country, every owner should arrange to inspect the keel and rudder whenever the boat is hanging in slings. At a minimum do the following:
• Wiggle/wobble test of both keel and rudder, especially after grounding. Watch this video of a typical Australian “wobble” test which shows alarming movement and visible cracks.
• Observe any lingering dampness/weeping after a haul out, which can signify an internal structural issue. If your rudder has a metal shaft, note lingering dampness where the shaft exits the rudder blade.
• Be aware of problems with boats of similar design, which may indicate concerns with a particular class, design or builder.
It is your responsibility to ensure your underwater appendages are as structurally sound as the rigging above deck that you see every day. Maximize your chance of reaching your destination safely rather than suffering the losses shown here.
Source: World Sailing