Riding out a storm, sealed up tight down below. Watch out for CO2.

[MartinR]

Water will get in, until it has compressed the air enough that they are in equilibrium. Also, air leaks much easier than water, so it can escape by way of the washboards for example, or the kitchen sink drain, if not closed.

Eventually there will be equilibrium and the boat can not sink due to this.

But it will add to the problems encountered after righting. There is water to get rid off, the water will probably have killed most of the electronics. This in addition to being dismasted of course.

We have to live with this, but ideally the Dorades would be tight inverted.

I might be wrong, though, not too much water intrusion in this test. Probably enough to kill the electronics, though.

https://www.youtube.com/watch?v=Gqe1Sxa2GXo

[Cpt Pat]

Originally Posted by MartinR

They write that the vents seal when inverted, due to water flow. There is a video of an inversion test on their site.

Completely inverted and turtled: yes. Knocked down on its side with the dorade submerged: no.

One could assert a cup is water-tight when carefully inverted in water. But turn it 90 degrees on its side in the water and...

[Cpt Pat]

Originally Posted by MartinR

He is ducting the air from his dorado ventilators down to cabin sole level. When the boat goes inverted, the outlet will be high above the water.

Unfortunately, this is not a solution easily implemented unless the boat is designed for it from the beginning.

Great idea! Ingenious! One could even run the duct all the way to the bilge to catch dribbles and install a side vent low on the duct close to to the sole to achieve a sort of double-dorade effect.

[Don C L]

I dunno Cpt, I think you and I, if we ever find ourselves in such a spot, won't see our ol' CCA boats stay upside down too long.

[capn_billl]

Originally Posted by Cpt Pat

I can tolerate farts. It's becoming stupid from CO2 that concerns me.

I have an issue with one sentence from above: "CO2 concentrations in outdoor air typically range from 300 to 500 ppm." There is nowhere on earth that has a CO2 concentration below 400 PPM - unless the air has been processed and scrubbed to remove CO2.

That quote above must have been written in the Good Old Days when ambient CO2 was much lower. Ambient CO2 hasn't been 300 PPM since before the 1960s.


(Primary Mauna Loa CO2 Record | Scripps CO2 Program)

Your graph shows co2 levels at the mouth of an active volcano.

The earth has several high, and low spots where co2 levels vary seasonally due to respiration from large forests.

It is currently considered the AVERAGE co2 as being 400ppm, but if the AVERAGE co2 is 400ppm, it stands to reason there are areas of PEAK CO2, and regions of LESS than 400ppm, to make the AVERAGE 400ppm.

[Singularity]

Originally Posted by Cpt Pat

...It's becoming stupid from CO2 that concerns me...

So is it correct that degraded cognitive performance/incapacitation is the main concern here? Of all the threats to cognitive performance/incapacitation on a sailboat, where do you place high CO2 in the rank list of threats?

If a CO2 alarm system is a countermeasure to the CO2 threat, what countermeasures would you employ to the other greater threats?

[Don C L]

Originally Posted by capn_billl

Your graph shows co2 levels at the mouth of an active volcano.

The earth has several high, and low spots where co2 levels vary seasonally due to respiration from large forests.

It is currently considered the AVERAGE co2 as being 400ppm, but if the AVERAGE co2 is 400ppm, it stands to reason there are areas of PEAK CO2, and regions of LESS than 400ppm, to make the AVERAGE 400ppm.

Mauna Loa and Mauna Kea are not erupting. The variations are on the order of 10 PPM, not 100 PPM. The top of a mountain in the middle of the Pacific is a pretty good place to collect air samples free of disruptions from forests or factories.
https://earthobservatory.nasa.gov/bl...oa-co2-record/

[hellosailor]

Must call Casio and Garmin. Surely one of them makes a wristhwatch with CO and CO2 detectors in it?

[Cheechako]

My guess is it’s a non risk. If it’s a storm that you really have to be sealed up tight below, boats have plenty of gaps through which air is pouring in along with water. My 47 footer was leaking a few places in lying a hull and those places never leaked before. It’ a blowing 60+ right? Lying shill is a bad option anyway, ypu’ll End up having plenty of oxygen while you are swimming!

[hellosailor]

One consideration on a boat is that they are rarely "sealed up tight". Every time the hull slams up and down in a storm, it gets squeezed and then expands again. The air gets forced out with every slam, and fresh air gets pulled in again. Submarines and fine steel builds excepted, perhaps.

[Cpt Pat]

Originally Posted by capn_billl

Your graph shows co2 levels at the mouth of an active volcano.

The earth has several high, and low spots where co2 levels vary seasonally due to respiration from large forests.

It is currently considered the AVERAGE co2 as being 400ppm, but if the AVERAGE co2 is 400ppm, it stands to reason there are areas of PEAK CO2, and regions of LESS than 400ppm, to make the AVERAGE 400ppm.

If the observatory is in the mouth of an active volcano, we'd better warn all those scientists who haven't noticed!

In all seriousness, the scientists thought this out: https://earthobservatory.nasa.gov/bl...oa-co2-record/






You are correct: there is some variation in CO2 concentrations by locale. Urban industrialized areas have higher than average CO2 levels. That's why the observatory was sited on top of a mountain surrounded by 1,000 miles of Pacific ocean - upwind of any local volcanic activity.

The average global CO2 level varies seasonally because there is more landmass in the northern hemisphere, so summer there causes plant life to absorb more CO2 than summer in the southern hemisphere. In a sense, the up and down variations you see in the graph is the earth "breathing" through vegetation. The last time CO2 was this high - vegetation returned it to an historic normal. The absorption process only took 50,000 years.

NASA now has a monitor in space. The lowest level they are seeing is 391 PPM.


https://earthobservatory.nasa.gov/im...carbon-dioxide

[Montanan]

Originally Posted by MartinR

He is ducting the air from his dorado ventilators down to cabin sole level. When the boat goes inverted, the outlet will be high above the water.

Unfortunately, this is not a solution easily implemented unless the boat is designed for it from the beginning.

An excellent observation Martin, which is why the engine room vents on the boats that I have been on have vent tubes that go clear to just above the floor and have a right angle jog beyond the centerline or even all the way athwartship or are fashioned in an X so that the water that may intrude through an open bollard vent would have to flow uphill in the tube to flow towards the exit of the tube just above the floor, what with the floor being the ceiling when turtled or sidewall when laid over 90 degrees on the side. This is simple to accomplish if you mount the vent tubes at a transom of the engine room or on a bulkhead wall in the inner part of the vessel.

I can't imagine installing a vent that does not have such simple yet totally effective system of routed air delivery with water intrusion mitigation.

The video sure shows the reason to keep the companionway door stoutly sealed. And the floor and hatch boards secured with strong latches. Heck even the pillows should be velcro attached to the supports.

Imagine the cutlery block full of knives upsetting and flailing the object about, or an unsecured and locked tool chest.

[Cpt Pat]

Originally Posted by Montanan

An excellent observation Martin, which is why the engine room vents on the boats that I have been on have vent tubes that go clear to just above the floor and have a right angle jog beyond the centerline or even all the way athwartship or are fashioned in an X so that the water that may intrude through an open bollard vent would have to flow uphill in the tube to flow towards the exit of the tube just above the floor, what with the floor being the ceiling when turtled or sidewall when laid over 90 degrees on the side. This is simple to accomplish if you mount the vent tubes at a transom of the engine room or on a bulkhead wall in the inner part of the vessel.

I can't imagine installing a vent that does not have such simple yet totally effective system of routed air delivery with water intrusion mitigation.

The video sure shows the reason to keep the companionway door stoutly sealed. And the floor and hatch boards secured with strong latches. Heck even the pillows should be velcro attached to the supports.

Imagine the cutlery block full of knives upsetting and flailing the object about, or an unsecured and locked tool chest.

... or an improperly secured battery. I've seen the results of that when crewing. Think "loose cannon." I've also heard of engines dropping off their mounts.

[barnakiel]

Except that sealing yourself down below is the best way to actually experience a knock down & roll over.


Who drives the boat when you guys are sealed down below? Or do you have one of those modern driver-less boats???


Cheers,
b.

[Montanan]

Originally Posted by Cpt Pat

... or an improperly secured battery. I've seen the results of that when crewing. Think "loose cannon." I've also heard of engines dropping off their mounts.

Ouch, definitely the batteries need latching down but they should only be able to go as far as the cables that tether them to the power electronics.

If the engine detaches, I think the boat would soon be done for. Talk about a flailing iron jib.

The chain locker hatch breaking open was a new one to me, I guess the hatch was not of robust manufacturing or installation. But there is a lot of weight is 200 or 300 feet of chain.

And lest we forget there being the keg(s) of beer, cases of wine and liquor bottles, and dive tanks and weight belts to contend with. There being 99 bottles of beer no longer on the wall.

Or the spare anchor(s) rattling about.

Of course if one turtles with a three hundred sixty degree athwartship roll, or a stern over bow roll, there is the strong potential of the mast being torn off and loads of water entering through the mast thence becoming a pipe to the keel step, or torn deck mounted mast step.

Jeez, this is all nightmare material. Going to need something to knock me out tonight.

Best wrap yourself in bubble wrap to contend with being tossed in the tumbler below deck. Going topsy turvy on deck would be no charmed life either.