Visual reference on anchor line

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Interesting.



The challenge when the wind has picked up during the dive is the reel/spool bouncing up and down with the waves. If you’re hanging substantially negatively buoyant on to the line when it’s bouncing then you’ll be lifted several feet and drop back down, this is very uncomfortable at least and can be dangerous should the line part and you quickly sink.

This comment and few others you made are inconsistent with my experience (which, admittedly does not include deco in large swells). The line we use has a strength of at least 100 lbs and the weight necesary to hold an smb up is on the order of 4-10 lbs. The line should not break and if it does when you are hanging from it, then it would be immediately obvious and corrective action would involve pressing a button and take less than 1 second, so line breakage is a non issue if you maintain the gear.

Also the idea of hanging for an hour fighting to hold the smb vertical for an hour in rough conditions should not happen. I always ask the captain to buzz the SMB when he finds it, reving the prop as he passes near, so I am re-assured that I am being watched and am not lost. Once that happens, the captain should not loose visual reference with the float, even if it flops over and you stop fighting to hold it vertical.

Also if it is rough, you can hold the reel down in front of yourself and and allow your shoulder movement to offset a few feet of vertical movement, very similar to how you hang on an anchor line when it is moving up and down.
 
I simply cannot imagine how uncomfortable it would be being bounced around in a moderate sea hanging negative on a line for an hour or more at decompression.
It takes only a small amount of line tension to keep a small SMB standing up. You don't need to be substantially negative. And because a small SMB doesn't have a lot of lift in the first place it doesn't bounce you around even in rough seas. As long as it's standing up it's quite visible to the boat crew even in such conditions (we have tested this).
 
And because a small SMB doesn't have a lot of lift in the first place it doesn't bounce you around even in rough seas. As long as it's standing up it's quite visible to the boat crew even in such conditions (we have tested this).
What are you calling 'rough seas'? The waves don't have to very high to make it very hard to see small smbs, especially in overcast conditions.
 
Sorry to say it like this, but small SMBs are useless in the sea. They're fine in confined waters or for training, but of no use in a sea.

Having said that, I now see why you attach an importance to getting it to stand up. It needs to be stood up so someone can see it from several hundred metres away. A large SMB laying down has size on its side and will show up in waves.


Yesterday, diving between the shipping lanes in the English Channel, I did 65 mins on the 45m/150ft wreck, with 60 mins decompressing. I put the SMB up from the wreck, where the boat skipper will be watching for my bag (he counts them up and expects one per diver). Then I floated westwards by about 2NM (2.2 miles/4km). Being the last bag up, he knows where I will be (2kt current from the wreck) and will run between the bags and picking up as divers surface, plus chasing off other boats who come to close to the field of bags.

Eventually there was only me. I could hear the boat nearby with the engine on tickover, as my deco ticked over - 30 mins left! But it was a calm-ish day with sunshine, so everyone had a nice time.


One other thing about SMBs is you always carry a spare SMB. That too must be a big SMB, in my case a Halcyon on a 60m spool.

You also need to write your name on it IN BIG LETTERS (with your phone number in case you loose it). The boat can read your name from a distance.
 
Sorry to say it like this, but small SMBs are useless in the sea. They're fine in confined waters or for training, but of no use in a sea.
I am curious about how you define big vs. small SMB and what other environmental factors are in place in your diving, especially OUT of the water, since @Nick_Radov said he tested both big and small SMBs and the latter work well for him.

OUT of the water means: the size of the waves, wind speed, fog/clouds/whatever else might affect visibility, etc.

@Nick_Radov, same I ask the same exact question for you :)
 
What are you calling 'rough seas'? The waves don't have to very high to make it very hard to see small smbs, especially in overcast conditions.
Just for a definition, a dive will definitely not happen if the wind is F5 or more (17kts+). It's largely up to the skipper, but if the waves get over about 1m/3'3" it becomes quite difficult to get back on the boat as you get battered around the dive lift -- you literally do handstands on the lift if hit by a larger wave.

The dangerous part is getting back onto the boat, not least tying things down on the decks and hoping divers don't slip over.

Obviously if the wind strengthens during the dive, you have to deal with what you get.
 
I am curious about how you define big vs. small SMB and what other environmental factors are in place in your diving, especially OUT of the water, since @Nick_Radov said he tested both big and small SMBs and the latter work well for him.

OUT of the water means: the size of the waves, wind speed, fog/clouds/whatever else might affect visibility, etc.

@Nick_Radov, same I ask the same exact question for you :)
1m/3ft and thin = small
1m20/4ft and thin = small

1m50/5ft and moderate girth = largish
2m/6ft and thick = large

You really shouldn't be doing longer dives in the sea with a small one!

Sea, meaning where there's some current and waves.
 
I am curious about how you define small vs. small and what other environmental factors are in place in your diving, especially OUT of the water, since @Nick_Radov said he tested both big and small SMBs and the latter work well for him.

@Nick_Radov, same I ask the same exact question for you :)
I actually agree with wibble here, the small smbs are useless in the sea. I doubt that Nick has actually tested it or has seen any conditions that you would consider 'rough seas' in northern Europe. Only 3 feet waves will make it incredible hard to see a smb that 3 or 4 feet out of the water. And you only see it for a second. And 3 feet waves are not 'rough seas' by any means.
 
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