Within the last fifty years there has been a significant number of high profile, catastrophic failures related to sail boat keels and the structures that are supposed to hold them in place. A small percentage of these failures have resulted in fatalities and have therefore been well documented. But most of the time when “keels fall off”, or come close to it, they are rarely heard about or discussed. The causes for these failures can be complex and are often a combination of factors as discussed below.
There are four primary causes for keels falling off:
I. Failing to reach an expected or required standard of engineering
- The designer or engineer fails to fully appreciate the loads on the keel and the structure that attaches it to the hull – a brief look into basic engineering principles and regulatory rules such as the ABS and ISO rule as they apply to structure associated with keels.
- The over-optimization of a structure so as to reduce weight (typically in race boats) while also not anticipating material fatigue and cyclic loadings with appropriate factors of safety.
II. Sub-standard building practices
- What can happen when construction plans aren’t followed (real life examples)
- The cost of fixing mistakes…do it right the first time!
III. Inadequate maintenance
- Putting a band aid on a gushing wound almost always leads to significant structural problems in the long run, and sometimes with fatal implications