Scamp LUNA was dismasted yesterday!

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dsimonson
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Scamp LUNA was dismasted yesterday!

Post by dsimonson »

Hello all, I just got back from a week of fantastic cruising, and breaking my mast. I've been asked for a report, so I thought I'd share a draft here. This might not be the final, I look forward to any comments, suggestions, and recommendations...

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Homeward bound after a week of cruising Howe Sound (just north of Vancouver, BC, Canada) in a small fleet of sailing dinghies, we left Plumper Cove mid-morning and were almost to Halkett Bay, our destination for the last anchorage of the trip. Approaching the Bay in our 12-foot Scamp, LUNA, on a starboard tack, outhaul almost block to block and downhaul hard on, we were beating into a very messy SE breeze. We had shaken a reef out before rounding Hope Point less than an hour ago, the wind had been very confused so we needed some power to keep going in the crazy shifts and lulls, but now it was stiffening and a squall was coming at us. Very black clouds approached quickly from the southeast, sheets of rain, building waves, and strong gusts hitting with vengeance.

We should’ve reefed again right away, but Heather in her 11-foot Mirror dinghy was right with us so I kind of hovered, luffing our big sail on a close reach, to make sure she survived. She almost went over in a powerful gust, but got her main dropped and started to look in control under her jib only as we approached the point of entering the bay. Now directly upwind of our destination, we bore off, and Chris fell back into my lap as LUNA lurched forward under a huge gust and we roared towards the bay. No way is this good! So overpowered with this full sail… gotta reef… rounded up, dropping the centreboard and sheeting in so I can tack onto port to reef (all my reefing cleats are on the port side of the boom… shoulda coulda woulda been better to just drop the sail and deal with them from the wrong side). As we rounded the bow through the eye of the wind the mast just blew up, yard and mast went over our starboard and boom over port side, we had a tent of a sail on top of us!

The tack of our lug sail was in front of the mast stub, Chris untied all the reefing pendants, and cut the tack lashing free from the boom while I released the clew, and cleared the sail from over our heads. We opened the forward hatches under the cuddy and pulled the the boom on board, stuffing the forward end into the hatch, then the mast, yard and sail on other side, and, once the rig was all on board and clear, we deployed the oars.

Meanwhile, Heather was well ahead, sailing downwind under her jib, and had pressed that red button on her radio just in case things did not go well for us.

A powerboat came up to us to ask if we were ok, because there was a mayday alert… I wasn’t really thinking clearly about it, in my mind we had just completed a successful self-rescue and a safe port was in sight directly downwind, so I signalled “no problem” and kept rowing in. (Chris was mad at me for not asking for a tow, anger spilling through her tension and fear, not a happy lady at this moment.)

It was hard to keep LUNA’s bow downwind in the big gusts, she really wanted to round up. But we soon arrived at the dinghy dock, the other three Mirrors ahead of us, everyone safe and sound.

As I was rowing in, I could see a big motor vessel heading into the bay with lights flashing on its cabin top, and then a Coast Guard helicopter was banking overhead, and the CG hovercraft appeared around the point!!

Holy! All sailors standing on the dock, mouths agape, and Heather tries to radio a stand down, no answer, and Chris tries our radio, gets through, the Coast Guard cutter arrives, and we give them the info they need… all safe, etc.

Examining the wreckage, the mast parted at the deck partner block on the forward side. That would’ve been the tension side of the structure when we came head-to-wind, the aft side under compression. The front three staves of the Sitka Spruce birds-mouth mast broke cleanly off right at the top of the partners, the remainder of the staves split vertically, lengthwise, not at any of the glue lines but between the glued surfaces. Perhaps the wood had a fault line at that point, but it’s more likely they just exceeded the designed structure tolerance. Totally understandable with the abuse I put them to! On the new mast, after consulting with the designer, I may increase the thickness of the staves slightly, and/or build in a bit of blocking at the mast partners.

Obviously I should’ve reefed right away, as soon as I saw that squall coming. Barring that, when I tore off downwind and found it too much, I should’ve let the sheet run, flagging the sail forward. That’s the beauty of an unstayed cat rig, but I’ve never done it before… too many years of sailing boats that the main pins against the stays… and that cost me a mast (and way too much excitement, and scaring the hell out of my wife, risking a marriage from lack of practicing a simple skill). Or, just round up to starboard and not sheet in, until the boat comes abeam of the wind, and drop the sail. It didn’t matter if the reefing lines and cleats were on the wrong side of the boom, once you’ve got the sail down you can just deal with the inconvenience. Sheesh. Live and Learn.

Regarding radios and emergency communications, I’m concerned. Our small handheld VHF does not have the “digital selective calling” (DSC) feature of the newer units. I like the longer battery life as it doesn’t have the built-in GPS required for DSC, but I do wonder if it’ll have that amazing response that the DSC provides if we ever really need help. Yes, Heather’s handheld DSC radio raised the emergency resources, but her depleted battery didn’t allow voice communication. Our radio did reach Victoria Coast Guard to tell them everyone was OK, but, that was after the fact. Would it have called out the troops if we needed them? How do we know? Should we carry both devices? or more? Or just rely on a DSC unit and carry bigger batteries for recharging it? I have the Coast Guard number in my phone “favourites” list, but have found a touch screen to be useless when sailing an open boat in trying conditions.

I feel awkward, embarrassed, and shameful that the Coast Guard appeared on our behalf, but certainly will not argue about a call if it appears a life may be in danger. I’m very grateful that Heather made that call! And feel terrible about my learning at so much expense.

Despite the series of missteps of the skipper, there was a lot of good luck in the whole episode. We had a fabulous week of sailing, we had great company, and within hours that company organized a rescue mission to get LUNA back home… We were lucky our mishap occurred so close to our destination. We were lucky we decided to include a camping tent in our stores to sleep onshore that night, then, the next morning, a friend close by to tow us to the nearest launch ramp on the mainland, and then a Mirror sailor at the ramp with a trailer to take us to our home port. We re-launched at the public ramp next to our moorage, and rowed her over to her parking spot. Loaded all the gear into our car and drove home, a little over 24 hours after busting our mast in a wilderness setting.
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Re: Scamp LUNA was dismasted yesterday!

Post by pocketyacht »

Hey Dale
Glad it all worked out.
Did you build your mast in a group build?
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Re: Scamp LUNA was dismasted yesterday!

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Whoa, that’s a huge adventure! Dale, I’m glad it worked out okay. A good write-up and lessons learned for all of us.

Let’s see now. Our 2017 R2AK Haro Strait adventure in my Noddy, an active participant in Dan Thompson’s 2019 Palooza beach episode, and now your current adventure. That puts you at the top of the list for SCAMP adventure sailing, Howard and his Southern Cross not withstanding.

This year my plan was an upgrade to my old hand-held (2007) VHF to a new DSC model. Your report has clinched it. Noddy has all the battery power any small boat needs. Those new ones are small enough to fit nicely in a PFD pocket so it’s always at hand. FYI, with my mast-top VHF antenna for my fixed bulkhead mount VHF, I do carry a suction-cup mount rubber-ducky spare antenna if needed in a dismasting (Shakespeare 5911 Classic Emergency VHF Antenna).

Great news though that you and Chris are safe and I’m sure that Luna is only slightly miffed at your transgressions. After all, we know she enjoyed the romp while it lasted.

Simeon
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Re: Scamp LUNA was dismasted yesterday!

Post by dsimonson »

pocketyacht wrote:
Sun Jun 13, 2021 12:31 pm
Hey Dale
Glad it all worked out.
Did you build your mast in a group build?
Hi Howard,
Yes, it was at Northwest Wooden Boat School, 8 students built a mast each in a weekend workshop, October 2012 or so. A great experience, fantastic instruction, and I'm now confident I could build a new one. (However, I lack the shop to do it in, I'll have to find someone to help with milling, and it might be a bit of a shade-tree assembly nightmare... haha)

I'm still sorting through photos, I'll post a few of the wreckage, soon. The break looks very similar to Brice's posted here a while ago.

John's design spec is for 16mm x 30mm stave dimensions at the base (tapering that 30mm dimension further up the mast). I'm wondering if I added a bit of thickness, increase that 16mm to 18mm or so, or, if I should put blocking in it at the partners (feathering the ends well, of course)? I'll have to shoot that question to John, but do you have any thoughts?

As mentioned in my "report," I believe the failure was entirely operator error, so maybe I should just stick to the original specs and learn how to take care of my vessel better! (Don't hold back, give it to me straight.) I was very careless, and forced the boat into an uncompromising situation.
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Re: Scamp LUNA was dismasted yesterday!

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Dale, here are my observations.

When you guys built your masts in 2012 under Bruce’s guidance at the NW Boat School, I noticed and later questioned that the interior of the staves during built-up were not pre-coated with raw epoxy during the glue-up. I don’t know, and doubt, that this had anything to do with your mast failure. On a future build I feel the interior of the hollow mast be pre-coated during assembly.

Josh’s SCAMP’s mast, built by Scott Jones at NWMC had staves that were 1/2” (12mm) in thickness. When I deflection tested the finished and already nicely varnished mast, we felt the mast was a bit limber and the decision was made to sleeve the upper 2/3rds of the mast with one of those stretchy F/G sleeves. 6oz cloth??? That is when Kees drew the Sheet-8 plans specifying 16mm (5/8”).

As far as I know, none of those early masts included any internal lower blocking (above and below the upper mast partner; blocking that would incorporate fish-tail stress risers at the upper end, as John Welsford does on many of his mast builds. I would add that on a new mast build.

Here is an earlier thread from SCA viewtopic.php?f=3&t=1553&p=13532&hilit=Staves#p13532
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Re: Scamp LUNA was dismasted yesterday!

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simeoniii wrote:
Sun Jun 13, 2021 1:44 pm
Let’s see now. Our 2017 R2AK Haro Strait adventure in my Noddy, an active participant in Dan Thompson’s 2019 Palooza beach episode, and now your current adventure. That puts you at the top of the list for SCAMP adventure sailing, Howard and his Southern Cross not withstanding.
Hi Simeon,
Yes, Howard's still at the Everest of that list. I'm just cresting a grassy knoll. I should still add a report of my losing the centreboard pin in Barkley Sound, out in the briny of the west coast of Vancouver Island. I've been meaning to write that up, might be some lessons for us there, too! But, now I'm a bit worried everyone will get the wrong impression about me, and run the other way...
simeoniii wrote:
Sun Jun 13, 2021 1:44 pm
This year my plan was an upgrade to my old hand-held (2007) VHF to a new DSC model. Your report has clinched it. Noddy has all the battery power any small boat needs. Those new ones are small enough to fit nicely in a PFD pocket so it’s always at hand. FYI, with my mast-top VHF antenna for my fixed bulkhead mount VHF, I do carry a suction-cup mount rubber-ducky spare antenna if needed in a dismasting (Shakespeare 5911 Classic Emergency VHF Antenna).
I recall not being able to reach the CG from Noddy via radio, you ended up calling R2AK race boss on your cell phone, and they used their race tracker to relay our position! These instances certainly shake confidence, so I think you're making the right decision. My 8-year-old "Standard Horizon HX300" works great for ship to ship line of sight, I replaced the OEM battery once, it charges with USB, and I can communicate with my comrades when we're on a group adventure. But, I think I'd better upgrade.
simeoniii wrote:
Sun Jun 13, 2021 1:44 pm
Great news though that you and Chris are safe and I’m sure that Luna is only slightly miffed at your transgressions. After all, we know she enjoyed the romp while it lasted.
She's a tough little boat with a heart of gold, and a blast to sail. When in company with longer, bigger, or, lighter, faster boats it's somewhat disconcerting to watch them stretch away from me, but I'm constantly pleased to be in her, and very glad of her comfort and capability. I arrive a bit drier, better fed, and more rested than many, and we bring many more smiles to everyone we meet!

Cheers,
Dale
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Re: Scamp LUNA was dismasted yesterday!

Post by dsimonson »

Thanks Simeon, great analysis.
simeoniii wrote:
Sun Jun 13, 2021 3:16 pm
...the interior of the staves during built-up were not pre-coated with raw epoxy during the glue-up. I don’t know, and doubt, that this had anything to do with your mast failure. On a future build I feel the interior of the hollow mast be pre-coated during assembly.
Agreed, not likely to contribute, but I'd do it on next mast.
simeoniii wrote:
Sun Jun 13, 2021 3:16 pm
Josh’s SCAMP’s mast, built by Scott Jones at NWMC had staves that were 1/2” (12mm) in thickness. When I deflection tested the finished and already nicely varnished mast, we felt the mast was a bit limber and the decision was made to sleeve the upper 2/3rds of the mast with one of those stretchy F/G sleeves. 6oz cloth??? That is when Kees drew the Sheet-8 plans specifying 16mm (5/8”).
Ah, I'd forgotten that history, good stuff. And the link to the earlier discussion. Thanks.
simeoniii wrote:
Sun Jun 13, 2021 3:16 pm
As far as I know, none of those early masts included any internal lower blocking (above and below the upper mast partner; blocking that would incorporate fish-tail stress risers at the upper end, as John Welsford does on many of his mast builds. I would add that on a new mast build.
So, it sounds like you'd keep the stave thickness at 16mm (5/8"), but include internal blocking at the partners. I'm guessing perhaps 12" of solid material centred at the partner location, with about 16" of fish-tail stress risers (love that terminology, it's perfect) above the solid part? None required on the lower end, as it's close to the step at the bottom... or ?

Loving the feedback, Simeon!

Hey, any thoughts or testing results on tinfoil in the mast? Derek and Keith both put it in but I didn't, but we've never had the opportunity for testing.

All the best,
Dale
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Re: Scamp LUNA was dismasted yesterday!

Post by simeoniii »

I’m guessing your guesses as to the blocking is about right. I may remember that John could have suggested just running it all the way down to the step end. Weight down low and all that. Maybe bounce that off John Welsford and report back to this thread for others to benefit from.

Howard had foil wadded up in his SC mast. When in Chile, the Armada Cutter was able to radar paint his vessel signature well so I guess that is good feedback.
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Re: Scamp LUNA was dismasted yesterday!

Post by Timo »

simeoniii wrote:
Sun Jun 13, 2021 6:13 pm
Maybe bounce that off John Welsford and report back to this thread for others to benefit from.
Yes, please, share with us John's analysis if he comments on the issue. It would be important to learn the lessons from this case. If structural modifications can prevent mast breakage in a similar way, then as many boat builders as possible should know about that.

I am glad that Dale made it back safely.
Sailing Wayfarer #8188 Sarastus and building Scamp #371 Merisirri in Finland
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