Would you dive to clear the prop?

Did it last w/e in the Orwell, swinging mooring and the tide in mid flood. Had a wet suit but no weights. Also I do some open water swimming in summer. Took 3 goes to free the prop and the cold makes your head hurt. Pouring warm water into the wetsuit just before you get in the water helps a lot, otherwise you end up gasping from the cold even with the suit. Its often a psychological barrier but if you are reasonably fit and a good swimmer then not a major problem. Just keep a suit and mask on board!
 
I managed to get an army surplus drysuit that I think had been stored but never used, for £80 on eBay. I also have a mask, snorkel, helmet, some weights (need to check how much I actually need in just a drysuit) etc. Haven't put this stuff on the boat yet but I am going to.

I know that in the past I definitely could have dived to the prop without too much trouble (we used to swim under the boat lengthways, in the med, and I retrieved a dropped watch from 12 metres under the keel) but it's fair to say I'm considerably less fit these days. I don't really want the hassle or volume of carrying breathing apparatus though. I should probably do a test run at some point.

Pete
 
It will happen! Sometimes,in bad sea conditions we leave well alone until the waves subside. We have a 'stripper' fantastic bit of kit that usually manages to cut through whatever is around the prop-can be a bit scary when the boat judders and the engine struggles but we have come through each incident OK(so far x).
Other half has been diving for over 30 years and we carry full kit on board-always ensuring the tank is full of new air when we set off on a long cruise or passage.
As we get older I have two rules: that he has to be able to dive under the boat to sort the prop and I have to be able to wind him to the top of the mast unaided, if we can't do that our off-shore days are over!
 
We have a homemade 'hookah' type system that can be used if we can't clear the prop using a snorkel. Just make sure that the ignition key has been removed so that there is no chance of anyone starting the engine up.
 
Champagne Murphy said:
Did it last w/e in the Orwell, swinging mooring and the tide in mid flood. Had a wet suit but no weights. Also I do some open water swimming in summer. Took 3 goes to free the prop and the cold makes your head hurt. Pouring warm water into the wetsuit just before you get in the water helps a lot, otherwise you end up gasping from the cold even with the suit. Its often a psychological barrier but if you are reasonably fit and a good swimmer then not a major problem. Just keep a suit and mask on board!
Click to expand...

Blummin eck - the water atm is freezing - it's bad enough just wading in to launch/recover the dinghy - I wouldn't want to go for a swim - wetsuit or not!

To the OP - whether or not I'd give clearing my prop a go depends on the circumstances. My longest sail is generally cross channel - and it'd have to be flat calm for me to even entertain going in.
Boat on the mooring and I'm more likely too - but probably having nipped home for a wetsuit first ... but then it's not that difficult to dry the boat out ...
 
I always carry a good mask and fins on my boat in case of any underwater drama, though she has an outboard in a well which usually prevents this.

The worst experience I've had was clearing a lot of weed from the prop of my Fathers' Centaur; it was in East Cowes marina in the old visitors part and I had to squeeze myself between the hull and the - err, ' mud ' as she settled.
 
I used the tube method with SWMBO last year.

She kept surfacing complaining that I had my thumb over the end.

I resolved the surfacing problem by keeping my foot on her head.
 
chinita said:
I used the tube method with SWMBO last year.

She kept surfacing complaining that I had my thumb over the end.

I resolved the surfacing problem by keeping my foot on her head.
Click to expand...

These women just don't know when they have a wonderful caring husband. Made mine do it naked so she wouldn't have to go to the trouble of drying the wetsuit out afterwards
 
A few years ago there was a device advertised for ' shallow water diving ', ideal for clearing props' etc; however I think it relied on an accumulator on deck, so best not try it after a marital row.
 
Some figures might help to visualise how hard it would be to breathe underwater with a tube to the surface.
The pressure underwater increases by about 1 psi for each 2 ft depth.
Clearing a prop will put your lungs about 2 ft down. The area of your chest is about 100 square inches.
So 2ft down, your chest muscles need to be capable of lifting 100 pounds each time you need to breathe in.
Try lying on your back with a sack of cement on your chest. Hard work!
 
Nostrodamus said:
We stood there watching her. Just a mouth piece attached to a length of tube. She was German though and might have been developed as the result of genetic mutation. She did tell us she had been free diving for years.
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As others have said the issue is clearing the tube of fouled air before taking the next breath - it's possible she's only breathing in via the tube, and out via her nose....
 
I have used the tube method 3 times now using a rope tied under the hull to help pull myself under. The first time the tube twisted half way through the dive, that makes you come up quick!
We have met people this year that are making up their own compressor and filter system estimating the cost to be around £400 but did not see them get to test it yet.
I would much prefer to dive at anchor than in a marina having seen the state of some of them.
 
nigelmercier said:
Quite hard do to, but I guess a one-way valve would help. I wonder if you could use a standard SCUBA DV?
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I can breathe in through my mouth and out through my nose no problem. Would be annoying if you're wearing a mask though.

The more significant problem as everyone has pointed out is the pressure difference. Snorkels only work because your lungs are practically awash as you lie flat in the water. If you hang vertically with just the tip of the tube sticking out (so a bit deeper than when swimming with head above water) you can feel the additional pressure making breathing harder. Go much deeper than that and it's impossible.

A demand valve won't work with incoming air at approximately ambient because the valve it comes in through is small. You need it to expand into the regulator to give you enough volume to inhale.

Some snorkels have a one-way valve at the bottom end for people who've never learned to clear a normal one. You could probably fit one of these mouthpieces onto an ambient-pressure supply tube to eliminate the tidal problem. Still won't help with the pressure.

Pete
 
nigelmercier said:
Quite hard do to, but I guess a one-way valve would help. I wonder if you could use a standard SCUBA DV?
Click to expand...

No a SCUBA regulator needs about 100-150 psi to operate correctly. The pressure balances the regulator spring. A HOOKA regulator is different (different spring) as it operated at about 25 psi

I have both SCUBA and a HOOKA set onboard. The water temperature where I an is very rarely less that 25 C.

This is my HOOKA set

http://www.powerdive.com/products/hookah/powersnorkel
 
nigelmercier said:
Quite hard do to, but I guess a one-way valve would help. I wonder if you could use a standard SCUBA DV?
Click to expand...

I think the clue was the bit about having been a free diver for years, so used to controlled breathing that most folk wouldn't be able to do even most divers.

I carry a 7 litre cylinder and stab jacket on board just in case having been diving for many years, but mid channel with the boat bouncing up and down, very doubtful I would get in the water unless it was to cut a crab pot line which was clear of the hull. The problem then comes if there is a tide running and the boat is anchored by the pot line, you could easily end up drifting off with the tide and the boat couldn't move. Classic accident pit senario.

Pete
 
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