Carbon Fiber Mast

Carbon fiber is basically laminated carbon sheaths, applied in layers and epoxied together with resin and heat and chemical hardeners, in this case to form a hollow mast. This mast needed "doublers" or extra laminated inserts inside the mast at the level of the spreaders. The pic below shows the gooseneck being reinforced with carbon laminates. The middle will be cut out to fit the boom. This is a typical area of cracking where the boom joins the mast, especially, after 2 years of downwind sailing, where the boom rocks up and down, despite the boom vang trying to stabilize the boom. 

 Here’s pics of the new and improved carbon fiber mast.

The crack you see is on a gusset or the diagonal protrusions from the mast. These need to be a lot stronger then when they come from the manufacturer if you plan to sail around the world, especially if they are carbon. Even the holes have to be a perfect fit, with bushings added to stop any play between the boom and the mast. 

The "GGR22" is the Golden Globe Round the World Solo 2022 'Retro' Race coming up this year. It's "retro",in that, the sailors have to use celestial navigation, can only use HF radio, and must sail a production boat built before 1988. You can bet that all these boats are reinforcing their masts, booms, and vangs. Some are shortening their masts and doubling the size of their standing rigging. We met Kirsten, the only woman entrant, on MINNEHAHA, who is parked near us. Checkout the GGR2022 on YOUTUBE.