Ditchable Weight

[fdog]

I'm not belittled at all, I think it's a valid point.

For me, swimming up weight is a tertiary answer to a buoyancy loss. I always have redundant buoyancy whether from a drysuit or a lift bag.

I think it's a valid number to know, because I know what my physical performance limit is, and never dive in a way that would exceed that.

I don't factor in a "emergency performance reduction", because this is essentially a single-point failure (loss of buoyancy), and if I'm in a dive scenario where other failures would be significant, I will be diving with teammates that are pretty adept at keeping failures from cascading.


All the best, James

 

[SteveAD]

What about a complete dry suit flood (think massive failure). I know it rarely happens, but If I was in my dry suit and diving, I would want to be able to ditch some weight if my suit flooded.

If the problem is JUST a drysuit flood then I would prefer to use my wing to get bouyant. If I had a drysuit flood AND a catastrophic wing failure simultaneously then I guess Mr. Murphy just really wants me dead.

 

[SkimFisher]

Can you achieve sufficient flotation on the surface if your wing fails? If you can then no need for ditchable weights. Your other option would be to ditch the rig. If you dive dry, you have backup. If you have double bladder as well.

Me? No. I don't float. Period. A lift bag\SMB works nicely as well.

Diving an HP100 with SS PB and 3mm wetsuit in salt water, I'm maybe heavy by a pound at the end of the dive. I could switch to an AL plate so I could wear a couple of pounds to ditch, but why. I should be able to swim up a couple of pounds. In event of a failed BC I do carry a lift bag or SMB. If worse came to worse, I could use this on the surface for support.

My one fear, which I haven't had to deal with yet, for real, is what would happen at depth if I had to doff and don my rig under water. Having a few pounds on me would be nice. Again, I can swim myself down.

There you go.

...and the doff/don problem is a problem for all of us who dive weight-integrated BC's whether the lead is ditchable or not. I've done it before in a pool setting and it's tricky.

I guess my question, to counter yours, is why are you so dead set against it? If it is secured and a diver can maintain trim and proper buoyancy, why is it such a issue? I feel a little like you are starting with the assumption that only inexperienced divers, or divers that are diving with less skill need to strap a little weight to their waist.

I didn't say I was dead set against it. I just question the preoccupation with it. As for the last part of your post - I really don't know how you came to that conclusion. Experience level has nothing to do with it.

My point in all this is that there are a few ways to get around a wing/bladder failure. One is the SMB you SHOULD be carrying anyways. Another is a lift bag rolled up and tucked in a pocket. There's also the buddy system as well - which I believe we've all heard of.

I would be interested to see just how buoyant a diver is at a depth below 40' once they drop weight. I bet you'd find that you're not as buoyant as you'd think.

Also - I don't think either way is wrong. Just discussion, folks. Dive how you like. I just think that in order for ditchable weight to really make a difference you've got to be a diver that requires a lot of weight to begin with.

 

[TSandM]

In the tropics, I have dived without ditchable weight. I know I can fairly easily swim up 10 lbs, because I have done it, and I will be no more negative than that at maximum depth on a single aluminum tank.

As described, with a dry suit flood, I use my wing, which has to have enough lift to cope with the loss of buoyancy from a flooded suit (and it does). I don't plan for two major failures on a dive (total loss of wing lift and dry suit flood).

I do think that new or inexperienced divers should have ditchable weight, because they are the people most likely to have problems and to end up on the surface frightened or panic-stricken. It's important to be able to render such a person quickly positive, IMO.

 

[Mike Boswell]

In the tropics, I have dived without ditchable weight. I know I can fairly easily swim up 10 lbs, because I have done it, and I will be no more negative than that at maximum depth on a single aluminum tank.

As described, with a dry suit flood, I use my wing, which has to have enough lift to cope with the loss of buoyancy from a flooded suit (and it does). I don't plan for two major failures on a dive (total loss of wing lift and dry suit flood).

I do think that new or inexperienced divers should have ditchable weight, because they are the people most likely to have problems and to end up on the surface frightened or panic-stricken. It's important to be able to render such a person quickly positive, IMO.

Here - at last - is the key point I have been missing, ever since I started diving again with cold-water gear.

The kelp-entangled Arizona diver (Forchione) who drowned off Point Loma last November after shucking his rig, but not his weight belt, would IMHO be alive today if he had had BCD-mounted ditchable weights.

 

[Bubbletrubble]

Here - at last - is the key point I have been missing, ever since I started diving again with cold-water gear.

The kelp-entangled Arizona diver (Forchione) who drowned off Point Loma last November after shucking his rig, but not his weight belt, would IMHO be alive today if he had had BCD-mounted ditchable weights.

@Mike Boswell: IMO, the DM who removed the guy's BCD (without first ditching the weight belt) deserves a significant amount of blame for that drowning.

So many things went wrong with that incident. There was a buddy separation -- and curiously the buddy either didn't attempt to look for him (using established lost buddy protocol) or didn't feel the situation was important enough to assist his buddy at the surface. The victim couldn't free himself from the kelp and probably managed his gas poorly for the given conditions (kelp divers know to pad gas reserves in case they have to re-submerge to get back to the boat). The DM probably didn't have adequate training to assist. The DM made a very questionable decision to remove the BCD without being 100% certain that he could establish positive buoyancy afterward. Very sad.

Sure, the DM might not have made such a fatal error if the victim were wearing all of his ditchable weight in weight-integrated BCD pockets. But I consider a weight belt to be a very standard method of carrying ditchable weight. AFAIK, nearly every OW student is taught how to use one. It's not unreasonable to ask that a DM look for one before ditching a diver's major means of floatation.

I agree that it's probably a good idea for novice divers to have ditchable weight in the form of easily-releasable weight-integrated BCD pouches, a weight harness with pull-handles (like the DUI Weight and Trim), or a standard weight belt.

 

[Scott L]

I hear a lot about "ditchable weight" and it always gets me wondering. I carry no ditchable weight - bc I don't need to. I dive steel 98's with 3lbs of trim weight in a 5mil. With the 3lbs I am slightly overweighted, but it helps me to trim out perfectly horizontal being that I am leg heavy. I'm blessed in the fact that I am a natural sinker. The fact that I have no ditchable weight doesn't really bother me, but I run across a lot of divers that seem very hesitant to carry no ditchable weight.

So I pose the following questions:

Do you consider it to be a necessity that a certain percentage of the lead you carry be ditchable?

WHY do you feel this way?

I get the impression that in some cases it's one of those "bc it makes me feel safer" mentalities without much thought really being put into it. Kind of like carrying a pony bottle (doh! I said it!). :shocked2:

Now obviously, those of you that need a lot of lead don't really have a choice. So this question doesn't really apply to you, though you may feel free to participate. I'm looking to those that dive BP's/doubles/or just don't need a lot of lead.

I assume you are using a steel plate?

 

[Jim Lapenta]

Here - at last - is the key point I have been missing, ever since I started diving again with cold-water gear.

The kelp-entangled Arizona diver (Forchione) who drowned off Point Loma last November after shucking his rig, but not his weight belt, would IMHO be alive today if he had had BCD-mounted ditchable weights.

He would also be alive if he had been properly trained and knew not to listen to a DM when it comes to removing gear. He would have known to tell the DM to go to hell and ditched his weightbelt and not his air supply. He would also have be alive if he had a decent buddy who stayed with him and was in position to assist. This incident and others is why one of the exercises I have added to my OW class in the rescue portion is the buddy supporting a diver at the surface for two minutes and assisting with removing their weightbelt. Having integrated weights is no substitute for good judgment, training, and common sense.

 

[iztok]

This incident and others is why one of the exercises I have added to my OW class in the rescue portion is the buddy supporting a diver at the surface for two minutes and assisting with removing their weightbelt.

I've been told and told during OW class to ditch weights on surface in such situation. Been drilled at Rescue class. I've seen it drilled when assisting Rescue class and seen it drilled assisting OW class. (I am only DMC so I mostly observe and do minor assists right now as I progress through DM program.)

Establishing buoyancy on the surface is being told and told again. Everyone can make a mistake but at DM level dropping weights should be the first thing during surface assist.

 

[LeadTurn_SD]

...
Do you consider it to be a necessity that a certain percentage of the lead you carry be ditchable?

WHY do you feel this way?.... [/I]

I don't feel it is necessary to have a certain percentage of ballast weight ditchable.

I do feel it is necessary to not be overweighted in the first place, and to be able to quickly establish neutral-to-positive buoyancy on the surface at the beginning of a dive. For many correctly-weighted single tank divers, this means being able to drop 6-10 lbs of their total ballast weight.

Can you keep your head above water with an empty BC at the start of a dive (basically, can you tread water with a full tank and empty BC)? If not, can you drop enough weight to do so?

Those are the things I consider when setting up a rig, and deciding how much ballast weight goes on a belt, and how much can be "fixed" on my backplate or tank straps.

Best wishes.

Edit: Some divers (my wife is one) will not require ballast beyond the weight of their rig... I still think the "can I tread water in this thing?" test applies. She has no problem (as an ex-National Team waterpolo player, I suspect she could do it without fins ).