Catamaran vs Monohull Crew Safety

[OldKetch]

Originally Posted by fxykty

The second big difference is that on cats the boom is generally not an issue. It is up high, there is a bimini roof between you and it, and the wide sheeting controls the boom even when well eased. Boom brakes are not required. Unexpected gybes do not sweep the deck. Preventers are used to stop flopping, but aren't needed to prevent the gybe.

With only a few thousand miles of cat experience (far less than yours) I have the impression that a Chinese gybe may have the same disastrous impact on the rigging of a cat. Hence, boom breaks may still make sense on a cat, even if an accidental gybe is less likely due to smaller propensity to sudden yawing.
Did I miss something or am I overly cautious?

[theBigKahuna]

One thing that I hadn't realized was simply tacking. We had an experienced crew working with us on our Leopard 40 (the captain being an ASA instructor), we all had to work through technique a couple of times... Cat's (esp larger ones) have A LOT of mass and 2 hulls, making it much more susceptible to ending up in irons (or I just suck at tacking!)

[StuM]

Originally Posted by OldKetch

With only a few thousand miles of cat experience (far less than yours) I have the impression that a Chinese gybe may have the same disastrous impact on the rigging of a cat.

On a cat, the main is sheeted out from the end of a very wide traveller. It won't travel as far or slam as hard as a fully eased main on a monohull.

[OldKetch]

Originally Posted by StuM

On a cat, the main is sheeted out from the end of a very wide traveller. It won't travel as far or slam as hard as a fully eased main on a monohull.

True, if the car is moved to the end of the traveller with a tightish mainsheet.
I saw many other setups too.

[mglonnro]

More of the anecdotal stuff on a Lagoon 52S, but... 50+ knots of TWS and the people in the cat are just like 'whooaa!'.. but standing inside in their normal everyday clothes without holding on to much anything.. and there is a free cup on the table

Well, downwind is downwind.

https://www.youtube.com/watch?v=njcbjnSMdH0

[44'cruisingcat]

Originally Posted by OldKetch

True, if the car is moved to the end of the traveller with a tightish mainsheet.
I saw many other setups too.

Most cat's will have either a wide traveller or double line sheeting with a wide base. Neither would allow the boom to move far if backwinded.

On our boat the boom could barely reach the centreline in an accidental gybe. And that's if I didn't have the preventer rigged, which can easily be done from the cockpit.

[mglonnro]

Here's another one

https://www.youtube.com/watch?v=WYHhDjWUEpY

[StuM]

Originally Posted by 44'cruisingcat

Most cat's will have either a wide traveller or double line sheeting with a wide base. Neither would allow the boom to move far if backwinded.

Both in my case

[contrail]

Originally Posted by theBigKahuna

One thing that I hadn't realized was simply tacking. We had an experienced crew working with us on our Leopard 40 (the captain being an ASA instructor), we all had to work through technique a couple of times... Cat's (esp larger ones) have A LOT of mass and 2 hulls, making it much more susceptible to ending up in irons (or I just suck at tacking!)

Not every instructor is experienced on cats. you shouldn't be ending in irons.

[Chotu]

Originally Posted by theBigKahuna

One thing that I hadn't realized was simply tacking. We had an experienced crew working with us on our Leopard 40 (the captain being an ASA instructor), we all had to work through technique a couple of times... Cat's (esp larger ones) have A LOT of mass and 2 hulls, making it much more susceptible to ending up in irons (or I just suck at tacking!)

It's actually the exact opposite. I remember transitioning from mnohull tacking to cat tacking.

It's because the Catamaran DOESN'T have much mass that tacking is hard.

On a mono the mass from the keel and the more aerodynamic shape keeps you moving through the tack easily.

On a cat, it's usually got a poor aerodynamic shape and little mass relative to the amount of hull presented to the wind. So it stalls mid tack. If it was heavier it would turn right through it like a monohull.

So.... The solution is to get plenty of speed on for a tack.

[thinwater]

Originally Posted by OldKetch

With only a few thousand miles of cat experience (far less than yours) I have the impression that a Chinese gybe may have the same disastrous impact on the rigging of a cat. Hence, boom breaks may still make sense on a cat, even if an accidental gybe is less likely due to smaller propensity to sudden yawing.
Did I miss something or am I overly cautious?

Yes, I think so (having experienced many accidental jibes on cruising cats). So long as you don't let too much sheet out, the boom is held down. Lock the traveler to leeward. With "cat" rigged shrouds, you should not have much sheet out, to avoid chafe.



BTW, many of these "accidental" jibes were intentional, testing the performance of boom brakes and jibe softeners.

[thinwater]

Originally Posted by OldKetch

True, if the car is moved to the end of the traveller with a tightish mainsheet.
I saw many other setups too.

Those other set-ups would be... wrong. At least in terms of safety. Heck, beach cats are sailed that way.

[44'cruisingcat]

An aspect of crew safety that's often overlooked is the dinghy. The ability to carry a good size dinghy and outboard, and launch and retrieve it easily is a real enhancement to safety.

[Juho]

Originally Posted by mglonnro

More of the anecdotal stuff on a Lagoon 52S, but... 50+ knots of TWS and the people in the cat are just like 'whooaa!'.. but standing inside in their normal everyday clothes without holding on to much anything.. and there is a free cup on the table

Well, downwind is downwind.

Isn't the summary of differences between catamarans and monohulls on crew safety that monohulls heel and sometimes roll, while the movements of catamarans are smaller. That may have an impact on head and shoulder injuries, and maybe on foredeck safety too. People may also get more tired if the boat movements are big and continuous, and that could make them prone to accidents.

A pilot house solves the "normal clothes" problem in monohulls.

[mglonnro]

Originally Posted by Juho

Isn't the summary of differences between catamarans and monohulls on crew safety that monohulls heel and sometimes roll, while the movements of catamarans are smaller. That may have an impact on head and shoulder injuries, and maybe on foredeck safety too. People may also get more tired if the boat movements are big and continuous, and that could make them prone to accidents.

A pilot house solves the "normal clothes" problem in monohulls.

That summary would seem likely (at least for a non-multihull sailor like me). The challenge, I think, is to actually establish this as some kind of a fact.

It's difficult.