Question about “balanced rigs” and having all ballast unditchable

[Dan_P]

Can any wetsuit configuration be "balanced" then, in your view?

Good question - and yes, absolutely!

A thick wetsuit can certainly be incorporated into a balanced rig, untill a certain depth (where compression will tip the scale) - the more neoprene, the less that depth. To make things a bit more clear-cut than that, I usually go by 18m for maximal depth in a wetsuit 5mm or thicker - that's a crude rule of thumb, of course.

One could easily argue that diving a 3mm wetsuit to greater depth is perfectly fine from a balancing perspective. I don't do that myself, but so long as a diver knows they're balanced, bene. Of course this applies to lycra, too.

Dive buddy is injured or incapacitated at depth, the same injury that incapacitated him damaged his BCD or dry suit. You are now responsible for getting him to the surface.

You now need to provide buoyancy for him and yourself. But, you both have your balanced rigs. Good luck getting him to the surface and keeping him there.

I don't see the problem, and effectively negotiate this routine very regularly, at demonstration level.

Your problem is a lack of imagination, not a lack of examples. Feel free to post an example of where having having a steel backplate with no ditchable weight increased a diver’s survivability. You asked for examples, you’ve gotten at least three... We are all waiting.....

I answered all of them above, including in particular my take on sending an unconscious diver off alone on an uncontrolled ascent.
And including a list of issues partaining specifically to the "uncontrolled ascent"-method.

 

[CT-Rich]

That's not a balanced rig, then.

Generally, thick wetsuits at depth aren't, due to the bouyancy swing brought about by compression of the thick neoprene.
But, we're aiming for thermal protection here, right? A thick wetsuit that's heavily compressed is really just a thin wetsuit, and not the intended thermal protection anyway.



If the wing isn't big enough to carry the diver, it's not a balanced rig.
But if we're looking at a - say - 21L wing, how is that not enough for two ali tanks?



I agree that the issue is lack of redundant bouyancy in both cases. A drysuit would do the trick.

And I agree that my view on ditchable weight should be seen in light of prerequisiting the rig is balanced.

From the surface, you need to get them out of a rig in either case. With ditchable lead, that's just one more thing to do.
From submerged, I wouldn't send an unconscious diver on an uncontrolled ascent on their own.

Dropping weight is increadibly quick way to make an unconscious or panicking diver positively buoyant on the surface. You seem to assume that a diver that ditches weight becomes a rocketship, when the primary concern is that with a flooded drysuit may be that they can’t even swim off the bottom.

Orally inflate the wing while using the donor's regulator.
Standard OOG training scenario, every time.

You are assuming you would not get separated from a dive buddy.

I do agree in that I also prefer to float comfortably. But that's separate from a question on ditchable weight.

I fail to see how ditchable weight and floating comfortably at the surface AREN’T separated. A lost diver waiting for rescue is going to want make sure their face is well clear of the water, especially if the weather is starting to turn.

Conversely, we see these reports about divers drowning because they "didn't drop their weight belt".
Risking AGE.
Risking DCS.
Risking surface traffic.

Balanced Rig is a universally applicable solution to the weighting/redundancy question, that's where it comes from and that's why it's used.

On a personal note entirely, I don't even bother selling jacket-style BCDs.
I see jacket-style BCDs in a contemporary setting as a marketing gimmick on par with split-fins, spare airs and those silly little rape-whistles people keep dragging along;

"Hold on, crack the window, I think I hear something"
- No rescue helicopter pilot, ever

My suspicion is that the universal cause of death will always be “his rig was not sufficiently balanced.....”

AGE, DCS are not guaranteed to occur because a diver ascended to rapidly. They can definitely occur, but ascent rates were twice as fast when I was certified than they are today. Breathing water at depth or on the surface is almost always fatal.

Boat traffic? Why does this keep getting mentioned? A diver low in the water is going to be less visible than a diver that is high in the water. This will increase the likelihood of rescue and reduce the likelihood of being run down.

 

[CT-Rich]

Good question - and yes, absolutely!

A thick wetsuit can certainly be incorporated into a balanced rig, untill a certain depth (where compression will tip the scale) - the more neoprene, the less that depth. To make things a bit more clear-cut than that, I usually go by 18m for maximal depth in a wetsuit 5mm or thicker - that's a crude rule of thumb, of course.

One could easily argue that diving a 3mm wetsuit to greater depth is perfectly fine from a balancing perspective. I don't do that myself, but so long as a diver knows they're balanced, bene. Of course this applies to lycra, too.

I don't see the problem, and effectively negotiate this routine very regularly, at demonstration level.

I answered all of them above, including in particular my take on sending an unconscious diver off alone on an uncontrolled ascent.
And including a list of issues partaining specifically to the "uncontrolled ascent"-method.

You keep assuming “uncontrolled ascent.” I don’t consider my dry suit 100% redundant because I cannot orally inflate it on the surface. On my rig, I can ditch weight in three batches. Two weight pouches and the belt when diving wet. When diving dry, I have two weight pouches on my BCD and two on my harness. If wanted to counter the negative buoyancy of the tank, I could do that in a split second. And weirdly, I don’t believe my rig is out of “balance.”

 

[Dan_P]

Dropping weight is increadibly quick way to make an unconscious or panicking diver positively buoyant on the surface. You seem to assume that a diver that ditches weight becomes a rocketship, when the primary concern is that with a flooded drysuit may be that they can’t even swim off the bottom.

Where are you getting this? There's no concern of not being able to get off the bottom with a flooded dry-suit, unless woefulle overweighted.
And inflating a BCD/BP-W is just as fast as dropping a weight belt anyway, without the downsides.

You are assuming you would not get separated from a dive buddy.

Yes, if an OOG diver makes it to the surface, I'm assuming they're not separated from their buddy.

I fail to see how ditchable weight and floating comfortably at the surface AREN’T separated. A lost diver waiting for rescue is going to want make sure their face is well clear of the water, especially if the weather is starting to turn.

Yet, they are.
Unless you're woefully overweighted, excess potential for bouyancy is significant in both wing and drysuit.
This is a non-issue.

My suspicion is that the universal cause of death will always be “his rig was not sufficiently balanced.....”

In many cases, but not all and not "universal", you'd probably be right.

AGE, DCS are not guaranteed to occur because a diver ascended to rapidly. They can definitely occur, but ascent rates were twice as fast when I was certified than they are today. Breathing water at depth or on the surface is almost always fatal.

DCS and AGE are "not guaranteed to occur"?
Great, I'll go to that shop for training.

Boat traffic? Why does this keep getting mentioned? A diver low in the water is going to be less visible than a diver that is high in the water. This will increase the likelihood of rescue and reduce the likelihood of being run down.

A diver who can't control their ascent is where the problem lies. A uncontrolled ascent has a higher risk of running up under a boat than a diver who can stop their ascent.
And why are we coming back to laying low in the water?
It's a non-issue unless one is carrying way too much lead.

You keep assuming “uncontrolled ascent.” I don’t consider my dry suit 100% redundant because I cannot orally inflate it on the surface. On my rig, I can ditch weight in three batches. Two weight pouches and the belt when diving wet. When diving dry, I have two weight pouches on my BCD and two on my harness. If wanted to counter the negative buoyancy of the tank, I could do that in a split second. And weirdly, I don’t believe my rig is out of “balance.”

Why do you feel you need to orally inflate your drysuit on the surface, if your rig isn't unbalanced?

 

[CT-Rich]

I’m done

 

[AJ]

To be honest: there's no fixing in this argument. Both sides have thier opinion and stick to it. Both sides have good arguments that work for them. So dive as you please, don't bother how others dive. There's no right or wrong here. Dive and let dive.

That's why I already stopped arguing

 

[Dan_P]

To be honest: there's no fixing in this argument. Both sides have thier opinion and stick to it. Both sides have good arguments that work for them. So dive as you please, don't bother how others dive. There's no right or wrong here. Dive and let dive.

That's why I already stopped arguing

I'm on about it still because OP asked why balanced rig. The question is answered, and loooooads of divers will continue to dive unbalanced regardless, as they have been doing for a long time already;
That's not something I can change with a forum post, they have to do that themselves if or when they want to - but the question is answered, which is what my goal was. Happy to leave it at that

 

[Storker]

loooooads of divers will continue to dive unbalanced

If I could be bothered to spend the time, it'd be... interesting to have a chat with you about what's right or wrong with my setup. Single tank BP/W, drysuit, thick undergarments, 16#/7.3kg non-ditchable, 12#+2kg (7.4kg) ditchable. Exclusively no-stop diving, and several (IMO) good reasons for having ditchable weight. Including the option of being able to ditch on the surface if the bovine manure should happen to intersect with the rotating ventilation device.

After all, we live in the same corner of the world. However, I believe I have better use of my free time.

 

[MichaelMc]

An example of a really bad idea/plan, but where the rig is balanced, so it should be fine, right?

<REALLY BAD PLAN>
Diving very negative.
Wing failure at 30' at dive start so swim to surface.
Able to swim up for the 60 seconds it takes to reach the surface, just.
So the rig was a balanced rig, and all will be fine. End of concern in planning?

Hot drop where boat was blown off drop site after divers enter.
Heavy swells and chop on surface. Hard to breath, or see the boat.

Tropics and neutral buoyancy suit, so no lift gained as ascended.
No ditchable weight, as rig is balanced....

Must continue to swim up harder to keep heavy head out of water and above chop as wait for boat to return or buddy to notice and come up as well.

Legs are burning with lactic acid... Really burning... Slipping lower... Coughing from waves....
</REALLY BAD PLAN>

Drowning is not fixable.

Balanced rig, able to swim it up, is very good idea.
Additionally being able to ditch some lead once you reach the surface is also a good idea. It does not make the rig any less balanced.
It is a separate and additional very prudent guideline.

 

[boulderjohn]

An example of a really bad idea/plan, but where the rig is balanced, so it should be fine, right?

<REALLY BAD PLAN>
Diving very negative.
...
Tropics and neutral buoyancy suit, so no lift gained as ascended.
...

Must continue to swim up harder to keep heavy head out of water and above chop as wait for boat to return or buddy to notice and come up as well.

Legs are burning with lactic acid... Really burning... Slipping lower... Coughing from waves....
</REALLY BAD PLAN>

First, I would first t like to point out that, like many of the other scenarios in this thread, this assumes the diver is significantly overweighted. The standard test for proper weighting is to be able to float at eye level with no air in the BCD and without kicking. Some people (not all) call for adding weight in addition to that to account for loss of air weight during the dive, but that should not be more than that anticipated air loss. In the tropics, that would be 5-6 pounds in almost all cases.

Next, the weight of the head is not important. It is the weight of the entire system (body and equipment) that determines buoyancy. If your entire system weighs less than the water it is in, then some portion of it (usually the head) will be above the water without any kicking at all. If the diver is carrying the full weight of the anticipated air loss (let's say 5-6 pounds), then that is the amount the diver must lift out of the water through kicking.