2788RE: [capri26] Re: Replacement Mast
- Nov 7, 2013
I do airplane crash investigations as a side line business and have numerous contacts as well as experience in metal fatigue. Can you post some photos and a diagrams what you remember to explain the failure?
I when I first read about it I assumed a fitting failed. With some photos we can all inspect the possible fracture location. Can you also explain the loads at the time of failure?
David L. Munson
MadMan Capri 26
Manchester, Missouri 63021
I’m not qualified to opine on the reason for the failure, but not being qualified has never stopped me from giving my opinion. Perhaps Bob Unkel and others who have a good technical understanding on our boat can speculate. I went back and inspected what’s left of the mast more closely. The mast broke above the spreader and fell to leeward (starboard side—we were on a port tack). The port spreader came off the mast, but the starboard spreader remained on the mast. No stays broke. The Starboard upper remained in the end of the spreader. However, the port upper came off of the port spreader which separated from the mast. Perhaps the port upper bounced out of the spreader, but if that is what happened, why did the spreader separate from the mast? I think the mast had metal fatigue and when it fell the tension on the port upper ripped off the spreader. Anyway, that’s the best I can do.
On 11/6/13 1:04 PM, "Robert Unkel" <bunkel@...> wrote:
Sorry to hear the news, but glad everyone is OK. Now doubt you were in a blow! Any info you can give us on mode of failure will help us all take appropriate countermeasures.
On Nov 5, 2013, at 11:19 PM, Gary Pack wrote:
Thanks for all of your responses and recommendations. I’ll let you know how it goes. I’ve had all kinds of thoughts on the reason for the mast breaking, but until an experienced rigger examines the pieces I won’t know for sure, so I won’t speculate now. Given the difficulty and sensitive nature of tuning our masts, I wonder if it is worth the investment of an inspection by an experienced rigger from time to time. I also wonder that given the age of our boats if it isn’t worth the cost of replacing all of the stays if they are 20 years or more old.
As to strength of the wind, the Race Committee was in open water a couple of miles away and they registered 37MPH. We were sailing upwind in a rather narrow channel and were at the end where it opened up to more open water. I suspect the wind was funneling into that channel at more than 40MPH, but I don’t have a wind speed instrument. We had eased our main and were pinching into the wind when the mast broke above the spreaders.
On 11/5/13 12:33 PM, "Randall Ferre" <rferre2000@... <x-msg://45/rferre2000@...> > wrote:
Sorry to hear about your mast. Glad to hear no one was hurt. How strong of wind? Any advice on prevention? Being a C26 newbie on a large mountain lake with some crazy winds at times (wind advisories sometimes gusting over 50kn, enough to blow a large BBQ 50 feet and rip a spa cover off and throw it over a fence and about 200 feet to the lake) your experience certainly makes me take note of the risk.
I recommend giving Catalina Direct a call. My experience has been very positive, even if they refer you to someone else or special order something. In some cases, their prices have beat West Marine.
Best of luck.
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