Why I Like Multihulls (Well, One Reason)

[bayview]

Originally Posted by cat man do

Would he have to?

My last 2 cats had nothing special in the way of rudders, both have sailed in through surf, the last one had been in similar conditions to the video and a much longer distance as well. ( Wide Bay Bar, 30 knots + on gusts and 5 metre waves and going in the long way)

Neither of them had any issue whatsoever tracking and steering across and down the face of waves.

Scary? At times, yes
Eyes like dinner plates? Most definitely

Heres a googled "5 meter wave". Remembering most big wave surf events require this minimum size to qualify as such. Your ride through that on a sail cat would have made an interesting video.

[Factor]

Originally Posted by Canibul

Stuff the bows of yer kittyboat with watermakers, generators, engine spares and extra fuel an try that again....

Why ever would you stuff the bows with that stuff, at any time.

[Factor]

Any way - you dont have to wonder about his thoughts or views, he wrote a story its published in the Australian Multi hull world magazine -

Here its is - just for you lot - courtesy of the editor of Multihull World - Australia - I tried to attach the pdf with photos and stuff - but it didnt want to play, the pdf file is available on the web elsewhere.

By the way - that very boat is for sale at the moment in South East Queensland.

PArt 1:

“We’re enveloped in an explosion of spray as the increasing speed of the boat smashes the wave everywhere, spuming through the trampolines, curling over the top of the bows, and racing down the gunwales. Everywhere except in the cockpit which remains completely dry. Conditions here are somewhere between exhilarating and orgasmic, at no stage do any of us feel any kind of fear, concern, or anything approaching a worry that we are in jeopardy. It’s simply the experience of a sailing lifetime, an adrenalin rush like none of us has ever experienced.”
SO IT WAS ON JULY 13, 2009 when I helmed my 12m catamaran, Saltonay over the Southport bar and made news headlines with the effort.
I have owned Saltonay for almost eight years ... Sailed her up and down Australia’s east coast and taken her as far south as Port Davey onTasmania’s rugged south west coast, in every way she is an outstanding vessel.
Bar crossings are a fact of life which every cruising sailor who travels Australia’s east coast will have to deal with at some point of their cruising career. The Southport Bar, entrance to Queensland’s Gold Coast, is a barred entrance which at times can be very dangerous and quite treacherous. Both these adjectives were used by the VMR obser vation post atop the Seaway Tower on the day Saltonay arrived to transit the bar.
Having now seen the film taken by a Channel Seven news team, I can easily understand why people seeing this vision are polarised in their opinions of me as a sailor. I decided to write this piece after I received a text message from a mate of mine. The text was meant as a humorous comment, but it had an impact. The message read. “Jesus loves you, everyone else thinks you’re a dickhead.

Part 2

The dramatic footage which was transmitted all around the world, I’m sure will recur in many ‘blogs’ and emails.
The fact is that a great deal of consideration and experience from the three crew aboard Saltonay culminated in the decision to make the entry.
Whilst this was the first time I had attempted to cross a bar when such a large ocean swell was in play, it was by no means my first challenging bar crossing, Yamba,Tweed Heads, Lakes Entrance and Wide Bay Bar into Fraser Island to name a few.
Two years ago I flew from my home town in Launceston,Tasmania to Lakes Entrance in Victoria, the location of what is probably Australia’s most dangerous bar, to undertake a two day course in bar crossing. This course gave not just theory, but involved practical instruction in a vessel which the students piloted over the breaking waves on the Lakes bar. The lessons learned here were put to use on the day I took Saltonay over the Southport Bar, adding worthwhile experience to my current Coxswains ticket.
It was now Sunday, we had departed Pittwater on the previous Friday morning at 6am. We sailed in a variety of conditions, none of which had been very challenging. The trip was a good one with enough wind to keep us sailing for the majority of the time, with the wind direction heading us only once for a couple of hours on the whole trip.
We sailed nonstop doing two overnighters and were offTweed Heads on the NSW border with Queensland, when we heard from the Seaway Tower that conditions on Queensland beaches and bars were dangerous. This was a result of a very deep low which had developed in the Pacific Ocean north of New Zealand some days prior, and now unusually large swells were hitting the coastline of eastern Australia.
This was not good news to us as we hadn’t expected this kind of hold up so near to the end of our passage.
We had no choice except to continue on, the bar at Tweed Heads was ever y bit as dangerous as Southport, and the next and closest safe entry would be Brisbane about 60 miles further, around the top of

Prt 3

Moreton Island, and then the same mileage back down the Broadwater to our destination on the Gold Coast.
We arrived off the Seaway Tower at around 4.30pm. Seaway Tower advised us that conditions were treacherous and we should not attempt an entry at this stage. It was just on low tide and the sea was really stacking up on the bar. We had virtually made our decision to carry on to Brisbane when Seaway Tower suggested that conditions may moderate in two or three hours as the tide came in. We then discussed the situation and decided to wait outside to see if the bar conditions moderated.
By 7.30 it was pitch dark and neither we nor the tower could tell if the seas were still breaking. We advised them that we would sneak up for a closer look to check this out. About 50m from the bar it became evident that the waves were very large and still breaking. We turned back out to sea and advised the tower that we would wait till around 10pm when the tide was getting closer to full
and we would have the assistance of a half moon for light. We returned at 10pm watching carefully and with a powerful spotlight to see if there was still breaking waves. Suddenly when only about 20m from the bar, a roar and an explosion of spray told me all I needed to know, so I turned tail and scarpered. It was clear that conditions were much less dangerous than we had observed earlier, it was also clear that to attempt an entry with very limited light would be just plain foolish, however the diminishing swell encouraged us to wait and try again in the morning.
We spent a sleepless night a couple of miles off shore slowly doing loops and circles while we waited for the dawn.
Just as it became light, a large motor cruiser called Capricorn Two called the tower to check on conditions for a transit through the bar. The tower said that the conditions had in fact improved considerably describing them as light to moderate. We, of course, felt a surge of relief; we would get in after all.
Capricorn Two then attempted a crossing but was unable to do so after a ‘heart stopping’ encounter with a large wave.
As the light improved it became clear that conditions, although much improved on yesterday were not as good as had first been thought. Seaway Tower revised their assessment stating that the bar was actually quite dangerous at times.
Capricorn Two hung around outside the bar watching for another opportunity to enter, and at around 9am she seized what appeared to be an opportunity and headed successfully in.
We then contacted the tower and indicated that we would come closer and make an attempt if the opportunity arose. It was my belief that if a large displacement cruiser with not much more motor speed than us could enter, then we should certainly be able to do so. The tower advised us that it was really difficult for them to advise us as the bar was dangerous at times and yet quite flat at times as well.

Capricorn Two then contacted us and informed us that conditions were quite difficult, and though they got through, they had almost come to grief as they had begun to broach, narrowly missing the wall before regaining control of the vessel.
We closed the saloon entry doors, donned life jackets (for the fourth time) then sat for about half an hour 50m back from the break, just observing the way the sea was behaving. The waves were coming consistently in sets of five, with the fifth being by far the biggest before a long gap and flat water prior to the next set. The smallest wave in the set was always the first and because of our limited boat speed of seven knots under power, I knew if I went for it, I would either just get all the way through, or I would have to contend with the first wave of the set, which in fact is exactly what happened.
The gap came and it looked good so we took the opportunity.
Our line through the bar was just exactly right, the water there was at its deepest and therefore the calmest. We were just about through when the first wave of the set caught us.
Catamarans, because of the great stability delivered by the two hulls, are far and away the best vessels to attempt a bar crossing, unlike monohulls they do not normally broach, and if steered correctly will track true through the breaking wave. Bouyancy up front and good sized rudders keep them out of difficulty in most cases.
Saltonay pointed her hulls down as the wave picked her stern up, there was no going back now, and we were well and truly committed. Saltonay vibrated with the most incredible and exciting noise as she roared down the face of the wave. Rodney, one of my two crew who has been sailing for about 50 years, said “Don’t look back Ian, just steer!”
We don’t really know what speed we were doing we were too intent on the situation to even think of looking at the log, but most seem to agree that we were doing in excess of 20kts.
This wild and incredible ride lasted only for 20 or 30 seconds, spray and water exploded all around the boat as the bows firstly bit into the face of the wave and then lifted as the buoyancy raised them, the rudders were doing their job as her bum tucked down and she tracked like a rocket on rails responding instantly to the corrections given by the helm. The noise inside the boat was like half a dozen bowling balls being bowled down a corrugated bowling lane.
As can be seen from the Seven News footage Saltonay handled the conditions brilliantly, at times she almost disappeared in a flurry of spray as the speed of the boat smashed the water everywhere. Water spumed up through the trampolines, curled over the tops of the bows and raced down the gunwales, everywhere except in the cockpit which stayed completely dry.
Conditions in the cockpit were euphoric; we screamed and yelled like banshees with excitement. This was way over the top in terms of thrill rides on the Gold Coast, at no stage of the ride did any of us feel fear, concern, or anything approaching a worry that we were in jeopardy. It was the experience of a sailing lifetime, an adrenalin rush like none of us have ever experienced.
Then it was all over, the water flattened out, and we heard a loud cheer from the end of the rock wall as the crowd which had gathered, obviously sensing a show, celebrated our spectacular entry.
On wobbly legs we cheered ourselves, relief, exhilaration and the hyper excitement of the adrenalin high pumping through our veins.
Seaway Tower came on the radio to welcome us to the Gold Coast.
“That was one helluva show, but you handled her beautifully” she said, “Congratulations Saltonay and welcome to the Gold Coast.”
It was then that we realised that there

was someone on the rock wall with a professional looking movie camera, and I said to Max Rawlings, one of the crew, that I would give important parts of my body to get hold of the film that was taken. Lo and behold, I received a phone call from Josh Adsett of Channel Seven, requesting an interview to go with the incredible footage his camera man had just shot.
Later that morning while sipping a well earned beer I turned to Rodney Smart, my other crew member, and asked, “Why did you tell me not to look back?”
He replied,“Mate you didn’t need to see the size of the bastard that was chasing us.”
Now that it is all over the inevitable question that begs an answer is of course,“Would you do the same thing again if the circumstance arose.” I have to say in all honesty, and the rest of the very experienced crew agrees, yes we would.
I believe we did our homework properly, assessed the situation accurately, and had the ideal vessel for just such a task. If one takes time to examine the film, it can be clearly seen that Saltonay at no time was in danger of burying her bows. Lots of foam, excitement and wild spray, but those bows were always clear of the actual waves surface, therefore preventing her from ‘tripping’ and pitchpoling from the following breaker. I have always made it law on board that there is nothing heavy stored in the bow compartments as this can ‘fight’ the buoyancy built in by the designer.
The only thing I would do differently is to make sure there are no news cameras around. I have at least another 12 months of lectures from my wife and my mum, both of whom were less than impressed. My dad however is as proud as punch ... Funny that.
The DVD of this bar crossing is available from Multihull World magazine for $20 including postage anywhere in Australia.

[Factor]

Originally Posted by bayview

Heres a googled "5 meter wave". Remembering most big wave surf events require this minimum size to qualify as such. Your ride through that on a sail cat would have made an interesting video.

Whats your point catty

[cat man do]

Originally Posted by bayview

Heres a googled "5 meter wave". Remembering most big wave surf events require this minimum size to qualify as such. Your ride through that on a sail cat would have made an interesting video.

Well I never ran out a tape measure to see how big it was, merely relied on what the coastguard told me and they said the bar was running at 5 meters.

Also the waves were werent breaking on a beach like your picture so did not look like that.

They had this sort of look

Untitled Document

Do you think a boat could sail in these?

They sailed in supposedly 12 metre to 20 metre waves in the tragic 1998 Sydney to Hobart
Reliving the tragedy that broke a nation's heart and changed the course of history - smh.com.au

Do you think they looked this?



GRAHAM RADFORD YACHT DESIGN - Stability Discussion

Or does your wild imagination think they would look like this?

[Joli]

By this read he did it the right way.

Originally Posted by Factor

Any way - you dont have to wonder about his thoughts or views, he wrote a story its published in the Australian Multi hull world magazine -

Here its is - just for you lot - courtesy of the editor of Multihull World - Australia - I tried to attach the pdf with photos and stuff - but it didnt want to play, the pdf file is available on the web elsewhere.

By the way - that very boat is for sale at the moment in South East Queensland.

PArt 1:

“We’re enveloped in an explosion of spray as the increasing speed of the boat smashes the wave everywhere, spuming through the trampolines, curling over the top of the bows, and racing down the gunwales. Everywhere except in the cockpit which remains completely dry. Conditions here are somewhere between exhilarating and orgasmic, at no stage do any of us feel any kind of fear, concern, or anything approaching a worry that we are in jeopardy. It’s simply the experience of a sailing lifetime, an adrenalin rush like none of us has ever experienced.”
SO IT WAS ON JULY 13, 2009 when I helmed my 12m catamaran, Saltonay over the Southport bar and made news headlines with the effort.
I have owned Saltonay for almost eight years ... Sailed her up and down Australia’s east coast and taken her as far south as Port Davey onTasmania’s rugged south west coast, in every way she is an outstanding vessel.
Bar crossings are a fact of life which every cruising sailor who travels Australia’s east coast will have to deal with at some point of their cruising career. The Southport Bar, entrance to Queensland’s Gold Coast, is a barred entrance which at times can be very dangerous and quite treacherous. Both these adjectives were used by the VMR obser vation post atop the Seaway Tower on the day Saltonay arrived to transit the bar.
Having now seen the film taken by a Channel Seven news team, I can easily understand why people seeing this vision are polarised in their opinions of me as a sailor. I decided to write this piece after I received a text message from a mate of mine. The text was meant as a humorous comment, but it had an impact. The message read. “Jesus loves you, everyone else thinks you’re a dickhead.

Part 2

The dramatic footage which was transmitted all around the world, I’m sure will recur in many ‘blogs’ and emails.
The fact is that a great deal of consideration and experience from the three crew aboard Saltonay culminated in the decision to make the entry.
Whilst this was the first time I had attempted to cross a bar when such a large ocean swell was in play, it was by no means my first challenging bar crossing, Yamba,Tweed Heads, Lakes Entrance and Wide Bay Bar into Fraser Island to name a few.
Two years ago I flew from my home town in Launceston,Tasmania to Lakes Entrance in Victoria, the location of what is probably Australia’s most dangerous bar, to undertake a two day course in bar crossing. This course gave not just theory, but involved practical instruction in a vessel which the students piloted over the breaking waves on the Lakes bar. The lessons learned here were put to use on the day I took Saltonay over the Southport Bar, adding worthwhile experience to my current Coxswains ticket.
It was now Sunday, we had departed Pittwater on the previous Friday morning at 6am. We sailed in a variety of conditions, none of which had been very challenging. The trip was a good one with enough wind to keep us sailing for the majority of the time, with the wind direction heading us only once for a couple of hours on the whole trip.
We sailed nonstop doing two overnighters and were offTweed Heads on the NSW border with Queensland, when we heard from the Seaway Tower that conditions on Queensland beaches and bars were dangerous. This was a result of a very deep low which had developed in the Pacific Ocean north of New Zealand some days prior, and now unusually large swells were hitting the coastline of eastern Australia.
This was not good news to us as we hadn’t expected this kind of hold up so near to the end of our passage.
We had no choice except to continue on, the bar at Tweed Heads was ever y bit as dangerous as Southport, and the next and closest safe entry would be Brisbane about 60 miles further, around the top of

Prt 3

Moreton Island, and then the same mileage back down the Broadwater to our destination on the Gold Coast.
We arrived off the Seaway Tower at around 4.30pm. Seaway Tower advised us that conditions were treacherous and we should not attempt an entry at this stage. It was just on low tide and the sea was really stacking up on the bar. We had virtually made our decision to carry on to Brisbane when Seaway Tower suggested that conditions may moderate in two or three hours as the tide came in. We then discussed the situation and decided to wait outside to see if the bar conditions moderated.
By 7.30 it was pitch dark and neither we nor the tower could tell if the seas were still breaking. We advised them that we would sneak up for a closer look to check this out. About 50m from the bar it became evident that the waves were very large and still breaking. We turned back out to sea and advised the tower that we would wait till around 10pm when the tide was getting closer to full
and we would have the assistance of a half moon for light. We returned at 10pm watching carefully and with a powerful spotlight to see if there was still breaking waves. Suddenly when only about 20m from the bar, a roar and an explosion of spray told me all I needed to know, so I turned tail and scarpered. It was clear that conditions were much less dangerous than we had observed earlier, it was also clear that to attempt an entry with very limited light would be just plain foolish, however the diminishing swell encouraged us to wait and try again in the morning.
We spent a sleepless night a couple of miles off shore slowly doing loops and circles while we waited for the dawn.
Just as it became light, a large motor cruiser called Capricorn Two called the tower to check on conditions for a transit through the bar. The tower said that the conditions had in fact improved considerably describing them as light to moderate. We, of course, felt a surge of relief; we would get in after all.
Capricorn Two then attempted a crossing but was unable to do so after a ‘heart stopping’ encounter with a large wave.
As the light improved it became clear that conditions, although much improved on yesterday were not as good as had first been thought. Seaway Tower revised their assessment stating that the bar was actually quite dangerous at times.
Capricorn Two hung around outside the bar watching for another opportunity to enter, and at around 9am she seized what appeared to be an opportunity and headed successfully in.
We then contacted the tower and indicated that we would come closer and make an attempt if the opportunity arose. It was my belief that if a large displacement cruiser with not much more motor speed than us could enter, then we should certainly be able to do so. The tower advised us that it was really difficult for them to advise us as the bar was dangerous at times and yet quite flat at times as well.

Capricorn Two then contacted us and informed us that conditions were quite difficult, and though they got through, they had almost come to grief as they had begun to broach, narrowly missing the wall before regaining control of the vessel.
We closed the saloon entry doors, donned life jackets (for the fourth time) then sat for about half an hour 50m back from the break, just observing the way the sea was behaving. The waves were coming consistently in sets of five, with the fifth being by far the biggest before a long gap and flat water prior to the next set. The smallest wave in the set was always the first and because of our limited boat speed of seven knots under power, I knew if I went for it, I would either just get all the way through, or I would have to contend with the first wave of the set, which in fact is exactly what happened.
The gap came and it looked good so we took the opportunity.
Our line through the bar was just exactly right, the water there was at its deepest and therefore the calmest. We were just about through when the first wave of the set caught us.
Catamarans, because of the great stability delivered by the two hulls, are far and away the best vessels to attempt a bar crossing, unlike monohulls they do not normally broach, and if steered correctly will track true through the breaking wave. Bouyancy up front and good sized rudders keep them out of difficulty in most cases.
Saltonay pointed her hulls down as the wave picked her stern up, there was no going back now, and we were well and truly committed. Saltonay vibrated with the most incredible and exciting noise as she roared down the face of the wave. Rodney, one of my two crew who has been sailing for about 50 years, said “Don’t look back Ian, just steer!”
We don’t really know what speed we were doing we were too intent on the situation to even think of looking at the log, but most seem to agree that we were doing in excess of 20kts.
This wild and incredible ride lasted only for 20 or 30 seconds, spray and water exploded all around the boat as the bows firstly bit into the face of the wave and then lifted as the buoyancy raised them, the rudders were doing their job as her bum tucked down and she tracked like a rocket on rails responding instantly to the corrections given by the helm. The noise inside the boat was like half a dozen bowling balls being bowled down a corrugated bowling lane.
As can be seen from the Seven News footage Saltonay handled the conditions brilliantly, at times she almost disappeared in a flurry of spray as the speed of the boat smashed the water everywhere. Water spumed up through the trampolines, curled over the tops of the bows and raced down the gunwales, everywhere except in the cockpit which stayed completely dry.
Conditions in the cockpit were euphoric; we screamed and yelled like banshees with excitement. This was way over the top in terms of thrill rides on the Gold Coast, at no stage of the ride did any of us feel fear, concern, or anything approaching a worry that we were in jeopardy. It was the experience of a sailing lifetime, an adrenalin rush like none of us have ever experienced.
Then it was all over, the water flattened out, and we heard a loud cheer from the end of the rock wall as the crowd which had gathered, obviously sensing a show, celebrated our spectacular entry.
On wobbly legs we cheered ourselves, relief, exhilaration and the hyper excitement of the adrenalin high pumping through our veins.
Seaway Tower came on the radio to welcome us to the Gold Coast.
“That was one helluva show, but you handled her beautifully” she said, “Congratulations Saltonay and welcome to the Gold Coast.”
It was then that we realised that there

was someone on the rock wall with a professional looking movie camera, and I said to Max Rawlings, one of the crew, that I would give important parts of my body to get hold of the film that was taken. Lo and behold, I received a phone call from Josh Adsett of Channel Seven, requesting an interview to go with the incredible footage his camera man had just shot.
Later that morning while sipping a well earned beer I turned to Rodney Smart, my other crew member, and asked, “Why did you tell me not to look back?”
He replied,“Mate you didn’t need to see the size of the bastard that was chasing us.”
Now that it is all over the inevitable question that begs an answer is of course,“Would you do the same thing again if the circumstance arose.” I have to say in all honesty, and the rest of the very experienced crew agrees, yes we would.
I believe we did our homework properly, assessed the situation accurately, and had the ideal vessel for just such a task. If one takes time to examine the film, it can be clearly seen that Saltonay at no time was in danger of burying her bows. Lots of foam, excitement and wild spray, but those bows were always clear of the actual waves surface, therefore preventing her from ‘tripping’ and pitchpoling from the following breaker. I have always made it law on board that there is nothing heavy stored in the bow compartments as this can ‘fight’ the buoyancy built in by the designer.
The only thing I would do differently is to make sure there are no news cameras around. I have at least another 12 months of lectures from my wife and my mum, both of whom were less than impressed. My dad however is as proud as punch ... Funny that.
The DVD of this bar crossing is available from Multihull World magazine for $20 including postage anywhere in Australia.

[imagine2frolic]

Thanks for the interview. It brings to light the preperations, and especially the training for the task. After reading the interview it doesn't seem so crazy of an act........i2f

[cat man do]

Originally Posted by bayview

Heres a googled "5 meter wave". Remembering most big wave surf events require this minimum size to qualify as such. Your ride through that on a sail cat would have made an interesting video.

Simple logic would show most people that this wave is not 5 metres high

Take note of the picture, if we said that the surfer is approx 2 metres tall and that the wave bottom is actual lower than the surfboard, it is clear that the wave is at least twice what catty/ bayview would have us believe..

[Canibul]

your 10 m mark is not at the top of the wave, either. And they get shorter when they break.

I figured five meters is a little over fifteen feet, or a little over two NBA basketball players stacked up.

That surfer crouched down isn't two meters tall,either, though. But you're right. that wave is a lot bigger than five meters.

[bayview]

Originally Posted by cat man do

Simple logic would show most people that this wave is not 5 metres high

Take note of the picture, if we said that the surfer is approx 2 metres tall and that the wave bottom is actual lower than the surfboard, it is clear that the wave is at least twice what catty/ bayview would have us believe..

So we can all understand what your idea is of a 5 meter wave is, check out this Beaufort like wave scale with pictures at the bottom of this article, noting the last picture is the 5 meter wave. You may find your interpretation of wave height is a little different to others.
See
Regards.http://www.yosurfer.com/content/mete..._wave_size.htm

[Jmolan]

I was just going to post the same idea. Surfers have always had a strange way of measuring waves (I know I is one) It's kind of a macho thing to under play it.....oh yea, it was 5 ft or so...yawn! And the other guy says, no way! those waves were double overhead man! And the macho guy and his buddies snicker at the gremmie and his buddies for being so scared.
Then you have east coast guys vs. west coast vs. Hawaiian etc. Then some smart guy wants to measure the waves backside. A 20' wave can have a 6' backside.
The tension will live on forever I think. And in boating it not far different. We alway try to look downwind in Alaska, it it will usually look nicer that way.

[Factor]

Okay - I'm bored with the wave size debate. Cat MAN Do reckons they were big going across the wide bay bar. whether they were 5meter or 4.7 really doesnt interest me, what does is that Cat Man do shared an experience with us that will be of assistance to any sailor who crosses the Wide Bay Bar.

Sheesh, catty stop picking on people just for the sake of a fight

[sww914]

Nice wave!
I would have cranked a hard bottom turn and snapped back up and hit the lip, bro.
Has anyone ever done a tube ride in a catamaran?

[cat man do]

Originally Posted by bayview

So we can all understand what your idea is of a 5 meter wave is, check out this Beaufort like wave scale with pictures at the bottom of this article, noting the last picture is the 5 meter wave. You may find your interpretation of wave height is a little different to others.
See
Regards.How to Measure Wave Size » Meteorology and Oceanography » Yo Surfer!

Perhaps you should be using the methods used by meteorology departments and govt. in Australia as it pertains to boating.

How do they work?
Waverider buoys are battery powered wave height measuring instruments. The waves are measured by an "accelerometer" in the centre of the buoy. The accelerometer in the centre of a Waverider buoy is an electronic device that measures the amount that the buoy is accelerated up and down by each passing wave. These measurements are converted into electrical signals that are transmitted by radio to the shore station for recording and later analysis.

Waverider buoys (Department of Environment and Resource Management)

[rabbit]

Being able to surf through somthing like this one of the safty features of a seaworty cat. however, doing so would be a 'last resort' for me!