The Jet Harness

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The Eclipse - as well as all of Halcyon's wings - have them on the left.

All commercially available wing designs have the inflator hose on the left, unless there is a double bladder... In which case there is an inflator valve on both sides... With the primary one being on the left.

Because of this, inflation is done with the left hand. If you dump using the hose, it's also done with the left hand.

A wing design with the bottom dump on the left has a superior design because if it's on the left, then all of the diver's BC controls can be operated with one hand. This leaves the right hand free to be occupied by whatever... An OOA situation, a buddy, a rescue, a light, a guage, an artifact, a slate/wetnotes, etc.

Having the BC's bottom dump on the right means that a diver must switch hands in order to operate all of his controls. Normally, this might not be an issue... But in the case of mucho task loading (especially during an emergency) the extra effort could make a problem worse.
 
Ok, but being devils advocate, isn't there something to be said for having the dump in the opposite position to the inflator ? I.e. the inflator being top left and dump being bottom right means that what ever you orientation, one of the dumps will work, e,.g. head up, head down, left up, left down ? whereas if both dumps are on the same side then if you are left side down for whatever reason then you wouldn't easily be able to dump air ?
 
There are some designs that use bottom dumps on both sides. They cite your above example as their reasoning.

It really depends on how you dive... I dive like this... Descend, get neutral, and use my lungs to maintain neutral buoyancy while at that level. If I change depth again for whatever reason, I might "dial in" my buoyancy again, but dumping and adding isn't something that I need to do often.

I also need to dump during ascent, and sometimes I need to touch my buoyancy once more during the dive as tanks change buoyancy.

So... Once during decent, once during acent, and perhaps once or even twice other than that during the dive.

...And at those moments I'm horizontal in the water column. Generally speaking, a left bottom dump, a right bottom dump, and even a hose dump would all work equally well.

...So I value the simplicity of having one dump that works, works well, and is always dependable. What I value is the "muscle memory" that I get from having and operating one good, solid dump valve placed in a reliable location. What I don't need are multiple dumps to choose from, or multiple failure points which I never use anyway.

Inflation, to me, happens on the end of that hose... Deflation happens at my bottom dump. The two actions are distinct, and very different... But both use the same hand. This makes them very easy to manage underwater while my brain is busy doing something else. The actions come automatically.

...So no, I haven't seen an advantage in having opposite side dumps, or a dump on the right side of the BC. But if you dive such that you're adding/dumping all the time, then you might want a dump on all four corners... One on each side at the bottom, a hose and pull dump on the left shoulder, and a pull dump on the right. Scubapro has this design.

I personally think that five dumps (two bottom, one on each shoulder, and one at the end of the hose) is asking for problems later on down the line, when the BC begins to age... So I'm not a fan. But some people are.
 
Likewise, I dump on descent and after that only when I rise in the water column, in other words....its not an elevator :) )

I think its a question of flexibility, if you always dive horizontal, and you always use the same kit config and the you dive at a level where you want to minimise task loading to the point that you want to only have one hand used for dumping, then you probably want the wing the way you suggest, but then again by that point you will have bought a halcyon, sleep with a long hose, have a DIR tattoo and changed your middle name to Jarrod. None of which is a bad thing (well?) but its only one type of diving.

Photographers etc in general don't want to stay horizontal at all times, and the variety of dumps they have available to them are more about what is most useful for a given orientation than simply a back up. So if they had to have 2 dumps then opposite corners make sense, if they can have 4 dumps then all corners make sense.

A someoone pointed out the wings with opposite dumps are in general those for single tanks whereas the more techie wings tnd to have them as you suggest, Horses for Courses.

(Sorry about the DIR bit, couldn't resist)
 
Conor once bubbled...
I think its a question of flexibility, if you always dive horizontal, and you always use the same kit config and the you dive at a level where you want to minimise task loading to the point that you want to only have one hand used for dumping, then you probably want the wing the way you suggest, but then again by that point you will have bought a halcyon, sleep with a long hose, have a DIR tattoo and changed your middle name to Jarrod. None of which is a bad thing (well?) but its only one type of diving.

Hahahahahaaaa!!! That's funny. :)


Photographers etc in general don't want to stay horizontal at all times, and the variety of dumps they have available to them are more about what is most useful for a given orientation than simply a back up. So if they had to have 2 dumps then opposite corners make sense, if they can have 4 dumps then all corners make sense.

A someoone pointed out the wings with opposite dumps are in general those for single tanks whereas the more techie wings tnd to have them as you suggest, Horses for Courses.

(Sorry about the DIR bit, couldn't resist)

Hey, no prob. :)

What I don't understand are the BC's that have only one bottom dump, and have it on the right side.

I mean, it's logical, at least, to have a dump on every corner of your body... It's not my personal choice, and I believe there are better solutions than having multiple dumps, but I can certainly understand the logic.

...But putting it right-side only gives the diver no more "flexibility" like you've mentioned that would be a desireable characteristic... Yet, the designer has removed the advantage that I claimed... Being able to operate everything with one hand.

...And I do agree with one thing you said... It's got to do with the type of diving you're doing... I prefer to call it the "style" of diving, and I know of people who call it their "philosophy" of diving. Whatever it's called, I think we're all basically talking about the same thing... Some people value the flexibility, while others value diving the same style in all of their diving.

It's a matter of preference. Both approaches are logical.
 
Analogy time (its friday)

You have a square fort and one sentry, where do you put him?
You have a square fort and two sentries, where do you put them?
You have a square fort and three sentries, where do you put them?
You have a square fort and four sentries, where do you put them?

Let me guess your answers
any corner
opposite corners
any 3 corners
all corners

This is the logic behind the opposite corner thing I guess.

To hungover to think of the other analogy for dumps on the same side but I'm sure there is one

It all comes down to different strategies, the one who comes out smiling is the one that got it right, and, unlike boking, in diving we can all come out smiling :)
 
Conor once bubbled...
Analogy time (its friday)

You have a square fort and one sentry, where do you put him?
You have a square fort and two sentries, where do you put them?
You have a square fort and three sentries, where do you put them?
You have a square fort and four sentries, where do you put them?


Lesseeee...

Square fort, one sentry: I buddy up with him, and we both climb to the top of the fort and watch over all sides, with two sets of eyes watching all of the sides of the fort.

Square fort, two sentries: Same... But with one sentry doing a perimeter "walk." Everyone stays in constant communication (using whatever means possible) and sticks to a consistent plan... Say, shift change every half hour or whatever, so nobody gets complacent.

Square fort, three: Each of us takes a corner so that we can all maintain communication with two others at all times, and there is a sort of "doubling up" of eyes on certain angles (each sentry being able to see 270* of horizon). Placing each sentry on a wall would not allow for this, and it wouldn't allow for communication between sentries.

Square fort, four: Same, but with one person additionally doing a perimeter walk for half an hour, then taking 15 minutes off so that they'll stay sharp... In a rotating pattern.

I'd also apply quite a bit of organizational theory to the mix, creating a highly cohesive, highly exclusive group so that the dynamics would be predictable... And predictably good.

How'd I do? :)
 
Oops, I'm talking mickey mouse tactics and get a lesson on fieldcraft.

Anyway I reckon we should patent the centre of wing dump and the migrating dump straight away, I like your thinking :)
 
Hahahahahaaa!!!

That's funny.

The bottom dump on a wing IS a center dump... Or rather, is very close to being a center dump.

When a diver is horizontal in the water, the wing "tacos" over the tank(s)... Making it's outside edge, which is curved, the center high point.

The problem is that there's two of them... One on the left side, and one on the right. Ultimately, a "bottom" dump on either underside of the wing, centered between top and bottom of the wing, would be the best place to have it.

However, in the interest of making the dump accessible to the diver, and to simplify the system, a right-side dump is forgone and the left side is moved down where the diver can reach it easily. Then the wing's edges are all rounded so that air travels freely inside the wing, making it easy to dump and making the absence of a right side dump moot.

A diver who then is neutral in the water column, diving a bp/wing which is also neutral in the water column then only needs to compensate for the change in buoyancy of his tanks over the course of the dive... Which is why it makes sense to have the air cell wrapped around the tank rather than being wrapped around the diver.

The diver may also have to manage a change in buoyancy from exposure suit compression at depth, but comparatively, it should be very little, or at least manageable through a dry suit inflator/dump valve.

...Which is why they recommend dry suits... Or, in the case of tropical waters, light wetsuits with only a couple of pounds of manageable buoyancy shift.

I'm flattered that you "like my thinking." I like yours too. I didn't always think this way, though... I was taught to think this way.

I don't know how to do the migrating dump, though. :D
 
I have been emailing Jeff form Jett Harness many times nitpicking him on every question and detail. He has responded promptly and professionally. He has been open to all ideas presented and will "custom" fit or make what ever my requests have been so far!!! He even volunteered me to compare his aircell to one I have already! So far he has been great! I will be using him to make me a "custom" Harness for my applications. When I get everything back I will post on their workmanship. I also am in the custom manufacturing business and listening to our customers and getting them what they want is the name of the game! It is refreshing to have new manufacturers "listen" and accommadate us especially in the dive industry where sometimes that can be the exception instead of the norm!!! Thanks Jet Harness and no I am in no way benefitting or trying to sell their product. Steve
 

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