F27 Beam failure

[Bunyip Bluegum]

A few days ago I experienced an aka failure while sailing my F27 which had been launched for the season the previous day. Conditions were wind about 15 kt, waves 1-2 ft. We were on starboard tack, on a close reach, doing 10-12 kt. with full main and a storm jib. There was a "crack" sound, and the port ama slowly folded out while the boat gradually heeled more to port and came to a stop.

Needless to say, this ruined my day. Nobody was hurt, but we had to be towed a few miles to the nearest harbor where we managed to call someone to bring the trailer. The boat was hauled out on the trailer (with significant difficulty), and towed back to the boatyard.

Neither I nor anyone I know has ever heard of this happening to any F boat. My contacts include The Multihull Source and the New England Multihull Association. If anyone knows of any similar incident I would like to hear about it. I'm also interested in any ideas about possible causes for this. The boat was in good condition and was well maintained.

I want to find a way to repair this, but it might be difficult for a number of reasons. This model has not been in production for more than 20 years. The molds for the akas do not exist. The design of the amas and akas changed over the course of production, so even if spare parts are available, they would have to be the right type for the earlier ama/aka design. Perhaps the best solution is to find an F27 available for sale that perhaps has been damaged in a different way such that I could make one good boat out of the two damaged boats. Any leads to that effect would be appreciated.

I wanted to include some photos, but I don't see a way to do that.  :mellow:  If it's possible, please let me know how to do it.

 

[ProaSailor]

There was a "crack" sound, and the port ama slowly folded out

What does "folded out" mean?  What cracked?  Where is the damage?

Yes, photos would help.  In the reply editor, see the "Drag files here to attach, or choose files..." at the bottom?

 

[Bunyip Bluegum]

The akas broke at the outside end. 

Thanks for the pointer to "Drag files here..." I don't think that was there when I composed the first post.

See photos. 

 

[djh]

Ouch! Sorry to hear about your breakage. I haven't heard of any similar incident myself. I would definitely get in touch with Farrier Marine to see what they have to say. I'm sure Ian would help if he was still alive, so you may find something there.

 

[Zonker]

Ouch indeed. Sorry to hear about this. I do recall something about F27 beam maintenance... separating of the flanges where they were glued together? Doesn't look like your failure mode though.

But it CAN be repaired. Much easier than finding new beams. Even if parts are missing. But it will be important to get a copy of the laminate schedule from a F-82 or F-9A builder to do it properly. Might add 10 lbs to the boat.

My friend drove his roof mounted kayak into an underground garage opening. Cracked 7/8 of the way around.

Before:

After. This was just me fixing it, with a sander, some glass & epoxy, epoxy filler and rattle can paint. It's actually really hard to fix thin laminates like this.

Part of the black coaming had disappeared and had to be recreated..But he thought it was a write off. $150 in materials later.

paint. 

 

[Zonker]

Were the securing bolts in place? Do the folding struts look OK?

Don't forget these were 2 piece beams made in a production facility. Avoiding any fairing is vital for production. Upper half/lower half, glue together.

But for a one off repair, you will have to do a lot of sanding - just takes time. It is repairable.

 

[Tri Therapy]

Steve Marsh who runs Finish Line, http://finishlineotc.com, in Florida may have “spare parts”.  He has picked up some damaged F27’s in the past or Don Wigston, also in Florida, runs Windcraft. https://windcraftmultihulls.com

the New England team you reached out to probably have reached out to them, they all are Corsair dealers.  
 

It is hard to tell from the pictures, but one looks like the Aka seam may have separated.....Ian has/had a bulletin probably moved to here: https://fct.groups.io/g/F-Boats/files which seems to have the old yahoo group archives.

Could you tell if one Aka caved first? Followed by cascading failures?

I would look up the bulletin and check the starboard side per the guide.

 

[Tri Therapy]

Here are two files from the archive that may be of interest

View attachment BeamCareBulletin.pdf
View attachment Beam void notice PH.docx

 

[plywoodboy]

Post a message on the groups.io F boats forum, you will get good advice and often spare parts.

I have the beam layup plans for all models if you need them.

 

[Zonker]

I think this picture shows exactly the type of failure described in the PDF file. Starts at the beam seam, hits the bolt hole (stress raiser) then  cracks the side and slowly peels the beam. IMO, the top of this picture is where the failure ended. It started at the bottom.

"Should the glue line fail here, and be undetected, the failure will grow along the join flange until it reaches a bolt, which then acts as a stress raiser.
A vertical crack running up the side of the beam may then develop from that bolt.
Now it gets serious and must be repaired without delay"

You may have had this sort of partial failure for a long time and just didn't see it. So this beam probably failed first and then 

 

[Bunyip Bluegum]

Zonker,

I was aware of the flange separation problem, and I thought it was being checked regularly. Initially there were no bolts in the flange. The bolts that are visible were later added because there was visible separation. This repair was done by the Multihull Source, who are very knowledgeable about these boats, and I trust they did it properly. In any case, I will re-inspect it with this in mind. There might be subtle clues that have been overlooked.

 

[Bunyip Bluegum]

plywoodboy,

I was told that molds for the akas are not available. Are there molds somewhere I haven't heard about? I'm not sure how the layup plans would be used without the molds. 

 

[Bunyip Bluegum]

Zonker,

Were the securing bolts in place? Do the folding struts look OK?

Don't forget these were 2 piece beams made in a production facility. Avoiding any fairing is vital for production. Upper half/lower half, glue together.

But for a one off repair, you will have to do a lot of sanding - just takes time. It is repairable.

Yes, the bolts holding the beam ends down were in place and tight.

Yes, the folding struts appear to be ok.

I'm not convinced that repair is practical. It would take some reconstruction, because some pieces were lost. A good sized chunk of core floated away, and I think a section of fiberglass and carbon fiber from the bottom side of the forward aka is gone. I question whether a repair could be as strong as the original.

 

[Bruno]

Ok, history of partial delam, added bolts, looks like some aluminum corrosion on the exposed mounts.

 

[Tri Therapy]

A Root cause investigation is important,  so is the sailing!   Check the starboard side for both cracks and the potential foam voids.   Ian mentioned effected hull id’s in the pdf.   Reach out to all the other Corsair dealers to search for potential parts......  this is not a do it yourself fibreglass repair at the component level, but if you can get a port ama with assembled Akas that obviously leads to the quickest return to water.  A few calls will set up realistic expectations for this hull.  There may be rig issues resulting from this failure.... check everything, twice to ensure you have a full understanding of the repair.

 

[Zonker]

I question whether a repair could be as strong as the original.

Sure it could. Because you're not using a female mould and creating a 2 piece beam, the new beam could be one piece foam core with the laminate just glassed over it.

But if you can find a new set of beams and maybe the ama, then that will get you sailing much faster.

 

[Russell Brown]

This has happened before at least once. My dear friends broke the front beam of their F-27 off the coast of Haiti and managed to tie the boat together to get in to port. Ian talked them through a repair. this was in the early 90's and the boat is still sailing. So sorry it happened to you. You have one of the "cool" ones without the flanges on the ama's too

 

[Justaquickone]

Is that expansion foam inside of the beams ?

 

[randii]

Sure it could. Because you're not using a female mould and creating a 2 piece beam, the new beam could be one piece foam core with the laminate just glassed over it.

But if you can find a new set of beams and maybe the ama, then that will get you sailing much faster.

FYI, this Zonker fella knows that of which he speaks. He's probably too modest  h34r: to call it out, but he is a working marine architect and made major modifications on a Woods catamaran that he subsequently sailed 'round the world with his family. You could hardly receive advice/assessment from better.

If he says it can be repaired, it certainly can be.  B)

Here's hoping you are repaired and back on the water quickly and safely!