Just got this off Scuttlebut (www.sailingscuttlebutt.com), sounded pretty good so I thought I'd pass it on. I could not get the image to come up but I'll try again. Let us know if you have any luck. SAFETY When a small sailboat capsizes, the masthead is immersed and water begins to intrude into the hollow core of the mast extrusion. This progressive flooding causes an increase in capsizing moment and the boat eventually turtles. When the boat is righted, the added weight of water must be lifted clear of the surface. Once the mast reaches horizontal, the water begins to flow toward the step. The reduced capsizing moment quickly drops well below the applied righting moment and the boat snaps through vertical, often to capsize again on the opposite tack. This could result in the crew becoming trapped under the sail, which is definitely not good. The Chicago Corinthian YC solved this problem on their 420s by inserting closed cell pipe insulation into the masts, at a total cost of the project was something like $6.00 per boat. The process with pictures is outlined on the CCYC website: www.corinthian.org/junior/Retrofitting420Mast.html