Join Date: Feb 2000
Location: Annapolis, Md
Thanked 140 Times in 113 Posts
Rep Power: 10
Actually, spar failures are way down from the bad old day of spagetti aluminum spars. Back during the IOR, late MORC, and early IMS days, aluminum spars had gotten tiny and failures were quite common. The rigs of that period were so fragile that short-handed sailing on larger leading edge boats was nearly imposible.
Because carbon fiber spars are so light for their strength and so can have higher safety factors, initially, they actually tend to be much stronger and less likely to fail than the aluminum spars that they replace. Carbon fiber spars have had an excellent safety record.
Its not that carbon fiber spars are without some liabilities. They do take greater care in their fabrication, expecially in the methods used to make attachments to the spar.
Carbon Fiber is more fatigue prone than aluminum and so potentially carbon spars have a more limited lifespan. That said, back in the late 1990's, I began hearing projections of 20-25 years for the early carbon fiber spars. That proved to be too conservative with many early non-grand prix carbon fiber spars approaching 30 years of use and still holding up.
One of the rarely discussed potential liabilities of a carbon spar is the impact of a lightning strike, which alledgedly, depending on who you believe, can greatly reduce the strength of the spar and accelerate fatigue.
The last issue is ease of repair. Carbon fiber spars are harder to repair than a damaged aluminum rig which may be repairable. This last issue may be a bit of a red herring since damaged aluminum spars seem to be repalced rather than repaired these days.