Hogarthian rig balancing

[Bob DBF]

posted on its own



Bob

 

[KevinNM]

I don't mean to be disrespectfull to G.I. And the whole DIR philosophy regarding using steel tanks wet, but this statement is utter rubbish.

IIRC, George Irving ran the body recovery operation after the Divers Supply disaster. He wasn't just making **** up, people have died doing this wrong. There is a huge set of threads on the old techdiver list archive on what happened if you want to look into it.

 

[DevonDiver]

I don't mean to be disrespectfull to G.I. And the whole DIR philosophy regarding using steel tanks wet, but this statement is utter rubbish.

It's based on accident analysis....

Wheras your counter-argument seems based entirely on economical and convenience factors.

Regardless if a diver is using a steel or aluminum tank, their OVERALL weighting is balanced accordingly, and as long as the diver (IMO) has enough ditchable weight using a steel tank to reach the surface and still not be too heavy at depth there is absolutely no difference.

First thing to remember is that DIR tends to favor a 'beginning with the end in mind' philosophy.

That said, the DIR balanced rig concept makes much more profound sense when considered in a technical diving context. It does so because the dive can be 'split' into phases, whereby intrinsic buoyancy, decompression obligation and weight of gas carried have an impact on each-other.

Initial Phase: Highest weight of gas carried (most negative), but zero or minimal deco obligation. You can jettison full deco/stages to get yourself at/near neutral for a controlled ascent.

End Phase: Lowest weight of gas carried (near-neutral), but you must complete deco obligation. Aluminum cylinders, at minimum gas, provide buoyancy for a controlled ascent.

In the end, the result of being able to hold a stop at 15' with an empty wing and a near empty tank is what we're shooting for. The rest of the combo doesn't matter.

Why ignore all variables up until the very end-phase of the dive. The issue is whether you can swim up a rig at any stage of dive.

If you only focus on holding stops... you are dealing with simple weighting, not a balanced rig. You are ignoring how intelligently selected rig components can promote or deter your success in ascending from a dive, at any time, should you lose buoyancy from your BCD.

Diving steel primaries with a wetsuit could be catastrophic in the event of BCD failure. Those that dive wet steel, tend to overcome that issue by reliance on dual-bladder/redundant BCDs. GUE/DIR have a reasoned argument against using dual-bladder BCDs; hence the need for a balanced rig and drysuit use...

 

[Eric Sedletzky]

It's based on accident analysis....

Wheras your counter-argument seems based entirely on economical and convenience factors.



First thing to remember is that DIR tends to favor a 'beginning with the end in mind' philosophy.

That said, the DIR balanced rig concept makes much more profound sense when considered in a technical diving context. It does so because the dive can be 'split' into phases, whereby intrinsic buoyancy, decompression obligation and weight of gas carried have an impact on each-other.

Initial Phase: Highest weight of gas carried (most negative), but zero or minimal deco obligation. You can jettison full deco/stages to get yourself at/near neutral for a controlled ascent.

End Phase: Lowest weight of gas carried (near-neutral), but you must complete deco obligation. Aluminum cylinders, at minimum gas, provide buoyancy for a controlled ascent.



Why ignore all variables up until the very end-phase of the dive. The issue is whether you can swim up a rig at any stage of dive.

If you only focus on holding stops... you are dealing with simple weighting, not a balanced rig. You are ignoring how intelligently selected rig components can promote or deter your success in ascending from a dive, at any time, should you lose buoyancy from your BCD.

Diving steel primaries with a wetsuit could be catastrophic in the event of BCD failure. Those that dive wet steel, tend to overcome that issue by reliance on dual-bladder/redundant BCDs. GUE/DIR have a reasoned argument against using dual-bladder BCDs; hence the need for a balanced rig and drysuit use...

I re-read the OP's initial post and I do not see anything about him diving in a technical context.
Most of us around the world dive in a recreational single tank context and stay within recreational depths. The extreme scenario both you and Kevin are describing doesn't describe 99% of the dives people around the world are doing. Do you realize that if everyone adhered to GI's blanket statement that nobody should ever dive steel tanks in a wetsuit that there probably wouldn't be any current steel tanks produced because sales would be so low that there wouldn't be enough sales to support production. In your technical environment I can see the exact reason for everything you are describing, but in a much more benign setting I think it borders on total fanatasism and becomes rediculous.
My whole argument is that regardless if a single tank recreational diver diving to moderate depths is using an aluminum 80 or a comparable steel tank, the end result weighting balance of tank gas plate (or no plate) weighbelt all even out. With an aluminum 80 and a regular bc equals a lot of added ballast. A steel tank with a backplate equals not so much added ballast, but in both cases it all equals out. It's not brain surgery. I don't think the OP is talking about doubles stage bottles caves etc. he's from San Diego and dives a single tank from a beach.
When that DIR protocol was written GUE was doing highly technical cave exploration. The whole reason for their existence was for cave exploration and the recruits that got into the whole DIR thing were being groomed for cave exploration. The entire program was reverse engineered so that from the beginning divers had the end result in mind of doing highly technical cave exploration. In our case of benign recreational dives we are reverse engineering the end result of our maximum diving intentions which is just to have fun and not diving to extreme depths, and staying way within ndl's. There are no stage bottles, no decompression, no doubles, none of that. So why would I reverse engineer my current setup from something that DIR extreme when I have no intention of reaching that result?
In my case and many others around the world diving wet steel within our parameters is perfectly safe.

Just to give you another tid bit, there is a school of minimalist divers that dive with no BC at all, so in a sense they have a permanent BC failure in that they have no BC. They are gliding around and having a great time, perfectly safe. And many using steel tanks. I've haven't heard of any yet that have been helplessly pinned on the sea floor until their death, probably because they were forced to figure out their weighting and maximum depth limits before undertaking that style of diving.

 

[DevonDiver]

I re-read the OP's initial post and I do not see anything about him diving in a technical context.

He asked about 'balanced rig'. That's a term coined by, and originating from, GUE. That de-facto includes factors that are very much 'beginning with the end in mind'... a holistic and systematic approach whose use is unilateral in all diving activities and throughout all levels, rec-to-tec.

Your argument is 'anti-balanced rig'. That's not what the OP asked for.

Balanced Rig isn't Hogarthian.... it's DIR. They aren't the same thing. The OP confused those terms.

A Hogathian rig need not be balanced. A DIR rig needs to be.

When that DIR protocol was written GUE was doing highly technical cave exploration. The whole reason for their existence was for cave exploration and the recruits that got into the whole DIR thing were being groomed for cave exploration. The entire program was reverse engineered so that from the beginning divers had the end result in mind of doing highly technical cave exploration.

Don't get me wrong... I'm not a DIR/GUE acolyte of any description. I've known about, investigated and 'cherry picked' from DIR for 15 years... but I don't believe in everything they specify. My point is to simply provide an answer for the OP, based on his question about Balanced Rig.

I think... and someone can correct me if I am wrong... that the GUE 'DIR' approach stems from the concept that if specific principles or approaches are "proven" more optimal for operation on high-level cave explorations, then they must surely be optimal for any type of diving. Basically, that 'Doing It Right' scales down to the entry-level. This also empowers novice divers to progress through levels without any significant changes in the protocols and configurations they use. Each level prepares for the next.

I've haven't heard of any yet that have been helplessly pinned on the sea floor until their death...

I agree.... but I think it's also wise to acknowledge that lessons can be learned, even as general principles, from the history of the wider diving community.

How many deaths would need to occur before an individual or local diving group would consider amending their diving practices?

How about incidents and near-misses?

BTW...anyone who's been active on Scubaboard for more than 2 years knows an experienced diver who died because of weighting/ buoyancy issues and being unable to surface (in very shallow water).

 

[Eric Sedletzky]

He asked about 'balanced rig'. That's a term coined by, and originating from, GUE. That de-facto includes factors that are very much 'beginning with the end in mind'... a holistic and systematic approach whose use is unilateral in all diving activities and throughout all levels, rec-to-tec.

Your argument is 'anti-balanced rig'. That's not what the OP asked for.

Balanced Rig isn't Hogarthian.... it's DIR. They aren't the same thing. The OP confused those terms.

A Hogathian rig need not be balanced. A DIR rig needs to be.



Don't get me wrong... I'm not a DIR/GUE acolyte of any description. I've known about, investigated and 'cherry picked' from DIR for 15 years... but I don't believe in everything they specify. My point is to simply provide an answer for the OP, based on his question about Balanced Rig.

I think... and someone can correct me if I am wrong... that the GUE 'DIR' approach stems from the concept that if specific principles or approaches are "proven" more optimal for operation on high-level cave explorations, then they must surely be optimal for any type of diving. Basically, that 'Doing It Right' scales down to the entry-level. This also empowers novice divers to progress through levels without any significant changes in the protocols and configurations they use. Each level prepares for the next.



I agree.... but I think it's also wise to acknowledge that lessons can be learned, even as general principles, from the history of the wider diving community.

How many deaths would need to occur before an individual or local diving group would consider amending their diving practices?

How about incidents and near-misses?

BTW...anyone who's been active on Scubaboard for more than 2 years knows an experienced diver who died because of weighting/ buoyancy issues and being unable to surface (in very shallow water).

Most entry level divers' deaths I've heard about died because of weight related issues of gross overweighting to the point that they couldn't even stay on the surface after a dive with an empty tank. In these cases they were seen on the surface in distress only to resubmerge and were recovered later on the bottom with weights still on.
In these cases it was just bad training on the part of weighting and the diver simply didn't have the proper info. If they did they would had to actually work to get down at the end of the dive with an empty tank and would have remained floating on the surface. This is where the concept of holding a stop at 15' with no air in the bc comes from in respect to using only the minimum amount of weight required for the dive. Any more than what's needed is just extra along for the ride and serves no useful purpose.
As far as DIR or GUE goes (all the same to me), I can appreciate their balanced rig concepts but I don't buy into the whole do it my way or die concept, and it seems this thread is headed in that direction.
Divers have been diving a long time before DIR and I think it's quite arrogant and pompous for anybody to come along and suddenly claim they are the foremost authority on everything diving. I'm not buying it.
Before GUE came along divers had other ideas what a "balanced" rig was, even though that exact term wasn't perhaps used, but the idea was there...And that idea was to have your weighting split up so that it was balanced between rig and weightbelt to allow for the rig to be removed at depth and both the rig and diver would remain neutral. This was the "balance".

I think having all weights attached in a non ditchable fashion is negligent and an accident waiting to happen. In the case of a bc failure and a simultaneous catastrophic drysuit failure, how do you deal with that? Impossible and will never happen you say, well there's a first time for everything and maybe it just hasn't happened yet. A wetsuit can't have a catastrophic failure (unless you take it off underwater) and a weightbelt can always be shed.

At this stage we can go back and forth but I don't really think it's going change much. All we can do is to agree to disagree.
Have a great day.

 

[DevonDiver]

In the case of a bc failure and a simultaneous catastrophic drysuit failure, how do you deal with that?

With a balanced rig.

That's the point of the thread.... which you're missing.

 

[seeker242]

So how much weight is considered too much for a rig to become unbalanced? Say you take everything into account, plates, gas, etc., and with that you are 10 lbs negative at depth, with a full tank, etc. Seems like that would be easy to swim up. But what about 15 lbs? 20 lbs? Is there a general rule of thumb as to how much is too much to swim up?

 

[KevinNM]

I've seen guidelines suggesting (IIRC) that something like 8-10 is where it gets very hard for most people. But just try it on your next dive.

 

[seeker242]

I've seen guidelines suggesting (IIRC) that something like 8-10 is where it gets very hard for most people. But just try it on your next dive.

I can swim my kit up pretty easily, I just don't know how heavy it actually is at depth. But that's using a single AL80 with 6lbs of lead in a 3/2 fullsuit. But if I switched to a 5mm in winter, or an HP steel tank, obviously that will change. I was wondering if there way a good way to figure it all out before going to depth and then finding out that no, it's not balanced. I would rather not ever be down there with an unbalanced rig.