Farr X2

[solosailor]

Keel socket laminated as part of the hull.

Sorry, that looks pathetic. My keel is a cassette retractable and the fin shape enlarges to a rectangle from the fin and goes up 2' into the hull under the nav seat. It has two large bolts holding HDPE or such as a way to keep it from falling out. My fin is carbon and structural from edge to edge with minimal fairing. And please tell me those hollow keel floors are tabbed, not just bonded down.

 

[Furkolkjaaf]

Now that looks a tiny pin, to take that huge bending moment...but what do I know. Glad crew are safe !

 

[LeoV]

I think the fin has a glass fairing over it.

Yep, that is common.

 

[Randomkiwi]

The cast iron part of the cassette only looks as wide as a thai boat builders thigh.

 

[Zonker]

The ballast is only 895 kg. So if you subtract the weight of the fin maybe 800 kg in the bulb? Fin is about 1.6-1.7m by eyeball.

Not exactly IACC or Volvo 70 bulb weight

 

[Randomkiwi]

How would the casette be attached to the hull once its slotted in? I was expecting to see some holes to take M16 bolts. I notice the caption is called clamping. Glued in?

 

[Zonker]

The cassette is the socket. I'd call the thing being inserted "the keel"

Very strong glue? Gorilla Glue perhaps? Just jesting.

Sure doesn't look like that fin has bolt holes in it does it? I don't think I'd just glue it in, no matter what the Plexus salesman says. I'm more of a bolt and suspenders guy.

Hmm I did bond on some carbon chainplates to my catamaran's mast beam using a fancy epoxy glue. It had lots of area according to the calcs. Then I laminated over it with extra layers of e-glass to hold it on because I didn't believe just glue

 

[minime88]

It appears to be bolted vertically, can be seen in photos of nav station on Facebook.

 

[Snowden]

From Team Nexba FB

STATEMENT

As our close followers may be aware, team 'nexba' capsized in the very early hours of Saturday morning. The team were completing a 100nm qualifier and had left Pittwater early Friday afternoon to be back in Pittwater by early to mid-Saturday morning.
Around 1am on Saturday morning as the team made their way home to Sydney in light to moderate breeze and 1-2m seas, the boat capsized. After spending 15hrs drifting out to sea with the upturned vessel, the team were rescued and are now safe on land, and have recovered in hospital with minor injuries. They are not yet ready to talk about their ordeal in a public forum and are grateful for space at this time. They will release a statement when they are ready.

The girls wish to say:
“Thank you everyone for your kind words of support, we are so grateful to have survived an awful ordeal and for our amazing community of family, friends, fellow sailors (basically family) and all of the incredible people who assisted in our rescue effort.
Thank you so greatly in particular to everyone who assisted in the team’s rescue effort, especially the incredible and highly trained team from the HMAS Brisbane, the crew of the Arietta Lily, the water police, marine rescue, 000 and the many parties who helped in communicating our position.”

A full investigation into the events leading to the boats inversion and the efforts made by the team to survive will be conducted so that others can learn from this experience and avoid such a terrible ordeal.

We will see you all on the water again very soon. xx

 

[Zonker]

Ah, those bolts makes sense. Perhaps somebody forgot the loc-tite?

You need some of those truck lug nut indicators. Or better yet, a means of positively locking the bolt heads. Safety wire anyone?

 

[Taipan]

From what we can gather from the articles, (early days I know)
The rescue was only launched after they didn't return and land based friends raised the alarm.

One could speculate that they didn't have an opportunity to raise a radio/phone/EPIRB/flare call out (likely in a sudden capsize) but what about PLB's?
Surely sailing short handed, offshore by them selves, you'd have PLB's attached to your (worn) offshore lifejackets etc.

Very luck they were found and live to sail another day. Well done to the Navy Crew.

 

[DickDastardly]

We still don’t know if the fin snapped or it just fell out however but SA tradition does not stop us reaching conclusions
Do they kit this thing out with cast stainless shackles?

So if we assume the moulded-in cassette didn't fail there aren't many possibilities: vertical bolts snapped or stripped their threads or the fin snapped, most likely at the highest loaded point - the hull junction. Seems pretty unlikely the bolts would unscrew.

I'd imagine inclusions or other casting imperfections in the fin are possible, as might be manufacturing process weaknesses such as accidental angle grinder cuts. If the fin snapped all will become clear. If the bolts let go, perhaps harder to diagnose - unless they're still in the boat and recoverable.

IIRC when Excalibur lost its keel off NSW many moons ago it was found to be a fin failure related to an angle grinder nick that had been welded up or something like that.

 

[DickDastardly]

From what we can gather from the articles, (early days I know)
The rescue was only launched after they didn't return and land based friends raised the alarm.

One could speculate that they didn't have an opportunity to raise an alarm (likely in a sudden capsize) but what about PLB's?
Surely sailing short handed, offshore by them selves, you'd have PLB's attached to your (worn) offshore lifejackets etc.

Very luck they were found and live to sail another day. Well done to the Navy Crew.

I'm surprised about that aspect. Look forward to lessons learnt from that. IIRC some of the older IMOCAS had an EPIRB porthole in the bottom for use in case of inversion, not sure if that's still common practice.

 

[PIL66 - XL2]

From what we can gather from the articles, (early days I know)
The rescue was only launched after they didn't return and land based friends raised the alarm.

One could speculate that they didn't have an opportunity to raise an alarm (likely in a sudden capsize) but what about PLB's?
Surely sailing short handed, offshore by them selves, you'd have PLB's attached to your (worn) offshore lifejackets etc.

Very luck they were found and live to sail another day. Well done to the Navy Crew.

Horrific ordeal and glad all are safe
Yep like you I am interested to hear why no PLB ..... No life raft...?

 

[RIGO]

Many inshore oriented boats sport the same keel head system - for example, the Ker11.3 (IRM Series from early 2000s) had the same cassette system with a single large high thread count bolt securing the keel head to an internal space frame. The cassette keel head has lots of advantages - it's very light weight, and it's very easy to keel on / off without the need for lots of the fairing work typical with the traditional keel tray. Never had an issue on the 11.3, and these have campaigned inshore and offshore all over the place - including a class win for Tow Truck in the S2H.

But - such systems that rely on few or even just one keel bolt require precise torque settings to be applied when fitting the keel - and this 'room for error' can certainly make you feel quite uncomfortable offshore. I would ALWAYS eye that single bolt at the top of the socket with a great degree of trepidation... I remember a Key West to St. Martin trip with several days of heavy air - slamming upwind - you know the sound - "SLAM->BRRRRRR, SLAM->BRRRR" over and over again - and I would sit below stewing, with that bolt under my hand, feeling for anything wrong - anything to tell me of any issues that would tell me to back off...

It's a given that this system is great for boats that race inshore, with lots between regatta logistics - but when something doesn't feel right for offshore sailing - you start to lose confidence. A solid keel structure, bolted to a solid internal structure (necessitating a LARGE hole in the boat for it to fall out) - with enough bolts for the possibility of some threads to fail and so on...

Perhaps in this case, it was the fin itself that broke, so this isn't a comment on what caused the Farr X2 accident, but rather its a reflection on the stress I have encountered when offshore, worrying about losing a cassette type keel - brings it all back...

 

[Kududine]

The change in shape from the keel to the insert wedge is extremely abrupt and a classic stress raiser. I cannot imagine how a famous design team could produce something like that. This is engineering design 101 type knowledge.

 

[mccroc]

I worry that this "new" interest in shorthanded sailing may potentially mean that in the rush to join this type of sailing, that there is not enough experienced people to help newcomers with the "nuts and bolts" of offshore sailing two-handed - which is really double solo-sailing. I do not know the offshore shorthanded experience of the crew, but towards the end of my shorthanded "career" I was always sailing with a PLB and a handheld VHF in my jacket, and my crew the same. We did not share any equipment, so in a similar case we would have had two PLBs and two VHF radios. In my boat, like this one, there would have been no time to get the boat's EPIRB, as it was down below, and therefore inaccessible after a capsize. Luckily whatever attachment they had to the boat could be easily released, after the capsize. There is no suggestion that they were out in bad weather, but the photo of them clinging to the hull - the saildrive leg I assume?, is chilling. Thankfully there was a saildrive, as with rudders and keel gone, what was there to hang on to?

 

[The Dark Knight]

Horrific ordeal and glad all are safe
Yep like you I am interested to hear why no PLB ..... No life raft...?

Maybe only renting for the race?

I have one Plb and 2xais mob’s. When I eventually race offshore I will as a minimum buy a 2nd Plb and rent the rest.

Personally, I think anyone who races offshore as crew on a regular basis should own their own Plb.

 

[duncan (the other one)]

Just to add to the speculation - original product brief was milled steel fin.

The new fast 30 by Farr Yacht Design

March 30, 2021 Sail World Announcement https://www.sail-world.com/news/227860 by John Curnow, Editor, Sail-World AUS 30 Mar 2020 08:00 AEDT The Mumm 30 as it was originally known, was designed by Farr. This is another crackerjack 30-footer from Farr Yacht Design (FYD); this time in conjunction...

www.farrx2.com

 

[pulpit]

View attachment 526783
From their Facebook page - here is how the keel is installed.

Farr X2

Farr X2, Sydney, Australia. 1,725 likes · 3 talking about this. The Farr X2 is the newest project by Farr Yacht Design to serve the Short Handed Market. Purpose built for optimum performance. The...

www.facebook.com

View attachment 526791

As a shipwright, I find it interesting looking at these photo's of the cast keel structure and bulb size.

When I look at it I'm amazed at how narrow the cast section is for and aft and then I look at how long the bulb is. The twist from the bulb when bouncing off waves to the fin would be a very big concern to me. I would be surprised if the fin is any thicker than about 60-90 mm at most and that's at the head of the fin and It looks like the fin narrows at the base as well.

This design is pushing the design envelop on the keel and fin that's for shore.

Pulpit