cheap halcyon gear

[jamiei]

2scuba, I'm 6'2, 175lbs and don't use anywhere near as much weight as you. With a 7mm full w/s, al bp (2lbs), heavy STA (5lbs), and an al 80 I only use about 8 lbs on my belt in freshwater and I can easily hold a 15 ft. safety stop at the end of the dive. Using that configuration with an empty tank, you should just slowly sink when you exhale. And when you exhale, you need to exhale fully. If you don't do a good full exhale, you're gonna be off and compensate by carrying too much weight. When you get down around 20 ft that suit is gonna compress and you'll sink much easier. Diving is much more enjoyable when you're not overweighted.

 

[-hh]

bandit_TX once bubbled...
If you can't slip one arm out of your Halcyon rigging without ducking underwater, you have the shoulder straps alot tighter than I do.

Personally, I find that if the shoulders & waist aren't firmed up, then you have the same "loosy goosy" tank roll-around problem as you get with a Jacket-style BC that has a soft backpack.

And for me, this issue is accentuated with UW photography, where I often have composition-based needs to be in an orientation thats far from the typical "perfectly horizontal" ideal for mere swimming. For example, if I'm choosing to do a reverse headstand to get my macro framer down into a barrel sponge for a cleaner shrimp, the last thing I want is for a loose system to slide 6" forward.

It allowed me to drop 8 pounds of lead, streamline considerably, {etc}

Was it really 8lbs of total ballast removed, or was it just that the ballast was shifted from being in the form of lead to being in the form of a BP?

Infosar as streamlining, its importance really depends on how you dive, and how far you need/want to travel. If you're on an OW drift dive, its simply not as important as a 3 mile cave scooter ride. In any event, I find that in carrying a largish dual-strobe UW camera system, how I choose to carry the camera is a lot more significant than any other piece of gear except for how many tanks I'm wearing. As such, things like BC-to-BC drag variations aren't a significant differentiation factor for me.

However, this "streamlined" claim is an interesting one because it is often quoted as significant despite the fact that there's no engineering data to back up the claim with quantitative proof. In a conversation elsewhere back in April, MHK actually offered to loan me a Halycon rig that I was going to use my professional Engineering contacts to get it tested as a Undergraduate Project at Steven's Institute of Technology (SIT) in their hydrodymanic test tank, which is the same facility that's used for developing the hulls of the USA's "America's Cup" sailboats. Unfortunately, MHK has not made good on his promise.

Problem is that the old Engineering Rule of Thumb is: "Without data, its merely an opinion", and the dive industry has all too many examples of grand product claims made without good quantitative testing to show if those claims are true, and even if they are, if they are significant enough to be a basis of product differentiation. And people wonder why I'm sometimes a grouchy diving curmugeon


-hh

 

[-hh]

jplacson once bubbled...
Wow...26# that's a lot though. I've never used a 6/7mm suit, so I can't imagine diving with that much lead on me.

Needing 25-30 lbs of ballast is pretty typical when you're wearing a 7mm (1/4") Farmer John. And more ballast is typically needed for larger and/or higher bodyfat divers.

A one piece wetsuit of the same thickness will require less ballast, but that's because they don't have the double layer over the torso. Its worth a quick ~6lb savings, but the trade-off is that they're not going to be as warm.

FWIW, you can also figure on a thick suit like this losing ~2lbs of its bouyancy after the first time you crush it on a coldwater dive to ~130fsw. Every little bit helps


-hh

 

[2scuba]

During my open dive in fresh water, I was wearing 7 mil farmer/john suit with 32lbs of weight around waist. At the end of the dive when my tank was at 1000PSI, I was floating like a cork - can't even sink.

In the salt water, I was wearing 26lbs of weight with a single 7-6-5 wetsuit. When my tank is at 150PSI and without air in the bladder, I was "neutrally buoyant" - when I exhale I sink and when I inhale I float .

Most of the dive shops mentioned 24lbs weights around my waist when I was shopping for my gear.

So I think 26lbs weight can't be too heavy for someone who is 175lbs, wears 7-6-5 wetsuit and almost empty tank

 

[SeaJay]

-hh once bubbled...


It is a YMMV...personally, I have a strong preference to stay away from running engines as much as reasonably possible, and all outboards in particular.

Ahem... Of course, I've never climbed a running motor. It needs to be off first. Sorry, I didn't mention that... I thought it would be common sense.

What does this have to do with a need for QD's?

To exit the water, you can:

1. Use a ladder.
2. Use my "leg throwover" method if the boat is small enough
3. Climb the motor.
4. Be hoisted out with a crane or SAR chopper.

Apparently, you prefer to do it without your gear. I prefer to do with with my gear. Either method works, with or without QD's, and in any combination.

...So I'll ask again... What does this have to do with QD's? And why have them and the potential problem with them if they don't make a diffference?

That head-dunking is pretty much the only way to get out of gear that lacks QD's, particularly if you want to have the tank/BC combo positively bouyant so that it doesn't sink and get lost as soon as you pull out of it.

Well, that's not actually true... You can chicken-wing out of it, too, exactly like a "regular" BC... Of course, someone already mentioned that...

And no, my rig's not "loosey-goosey."

But so what? Are you trying to avoid getting your hair wet or something?

Personally, I don't like this technique because it means that I must lose direct eye contact with the boat, which means that there's the distinct possibility of getting brained with the boat during those few moments that its tossing around in the water and you're unable to watch/anticipate (and protect versus) its every movement. YMMV, but I consider this to pragmatically be a higher system safety risk than a QD fastener failure, hence my choice.

Oh, fer cryin' out loud, -hh... Where do you get this stuff? Are you just sitting around making it up? Don't take off your BC UNDER the boat. Give yourself a little room... You should anyway. Working a QD close to the boat is just as dangerous as dunking out of a bp/wing close to the boat. The answer isn't to use a QD... The answer is to not be so close to the boat.

...Or better yet... Don't remove your gear before climbing into the boat. Exit while wearing it, just like everyone else.

Yes, but with lighter weight travel gear (no 8lb SS plate) and floaty Resort AL80 tanks, its no mean task to trim out a wing configuration such that it's not going to torque you face-down to some degree. I won't say that its impossible, but unless you have a keel weight pocket added to your BC strap to compensate for the lack of mass in a AL backplate that would otherwise be there with a SS one, its pretty darn close.

"Close to impossible to trim a BC that's not a SS plate?" Where do you come up with this stuff?

The SS plate is a "built in" advantage in terms of trim for most people... But a weight in a trim pocket of a better "regular" BC is a very close simulation... And not at all impossible.

On the snorkel, this divers distress was really due to illogically priortizing the modern "streamlining" nonsense over basic dive safety while on a clutter-free drift dive where neither entanglements nor streamlining are a meaningful issue.

Perhaps... I don't know... I wasn't there.

...But I can tell you that you have already told me that she had huge trim issues, and I mean, really bad ones. If she could not keep her mouth out of the water while floating at the surface, then I'd say there's a huge issue there. The answer isn't to use a snorkel... The answer is to fix the trim problem.

The underlying problem was that the workload task of deploying her snorkel (either on the surface, or on her safety stop prior to surfacing) exceeded her abilities due to other workload complications, namely an UW camera. Fortunately, the only thing hurt was her upper GI and pride. Unfortunately, she kept on making the same basic mistake, day after day, because she was following someone else's "optimized system" without objectively thinking for herself its applicability for her needs.

Well, apparently she needed more training. But because she was wearing a bp/wings, it suddenly became a bp/wing issue? What sort of fins was she wearing? If they were Volos, for example, why haven't you told everyone that Volos do not allow you to fin against your trim issues, and so therefore you're going to swallow lots of seawater?

It just doesn't make any sense,-hh.

In other words, the question that really must be raised was why she insisted on sticking with a system that obviously wasn't working.

Well, I would argue that the system wasn't the problem, but the way it was being used. Just like the concept of driving an automobile... It needs to be used properly to get the desired results.

IMO, this diver was absolutely determined to not wear a snorkel no matter what, probably because she was in "Monkey See, Monkey Do" mode, and the trend today is to copy the Cavers (note that she already had the wings).

I don't cave. In fact, I dive boats almost exclusively. Yet, I don't wear a snorkel... And it's not 'cause I don't know anything about them or am otherwise ignorant. But when diving, I leave mine on the boat.

Am I, too, "copying the Cavers?"

If we check out http://www.gue.com/equipment/equip-anatomy.shtml we find there's absolutely no mention of a snorkel at all.

That's because they promote proper buoyancy and trim in order to prevent themselves from swallowing seawater, not the "band aid" of putting a snorkel in their mouth.

Of course, they're not of much use in a cave, but this is merely just another example of how one configuration isn't optimum for all diving, regardless of what its proponents might otherwise claim.

I don't cave. Many DIR divers don't cave. Many cave divers who dive boats don't wear snorkels. While it's true that DIR diving was borne in caves, to assume there is no benefit to it's tenants in open water is shortsighted.

Bottom line is that being a follower only goes so far: you really have to think for yourself, objectively understand what your operational requirements are, and work accordingly.

You know, I hear this point all the time... The accusation of DIR divers being "followers." This is a completely incorrect and ignorant assessment. If you take two divers, equally trained by PADI or whoever and give them the same experiences and the same gear and the same everything... I mean, for a moment assume two identical divers. Now put one through a DIR class. Which one now has more skills sets to pick from? Which one has been exposed to more information? Which one has a bigger "clue?"

...And if the one that's never even seen the inside of a DIR classroom looks at the other and derrogatorily accuses the other of being a "follower"... Doesn't that sound like complete ignorance talking?

...So I pose to you, -hh... When was the last time you took a DIR course?

 

[SeaJay]

-hh once bubbled...

Was it really 8lbs of total ballast removed, or was it just that the ballast was shifted from being in the form of lead to being in the form of a BP?

-hh, your "standard" SS bp is just under 6 pounds, not 8.

 

[jamiei]

2scuba, I just don't see how someone my same weight would need that much lead unless their bc is trapping a lot of air or has a high percentage of body fat. I've seen much larger guys (240 lbs) wearing a 3mm full suit in freshwater not using that much weight. They didn't need a 7mm cause they had so much built in insulation.

If you were floating like a cork w/ 1000 psi and 32 pounds of lead, you must have had air in your bc. An aluminum 80 with 1000 psi of air in it isn't that positively buoyant and 32 pounds is a lot of lead for anyone.

 

[-hh]

SeaJay once bubbled...

Ahem... Of course, I've never climbed a running motor. It needs to be off first. Sorry, I didn't mention that... I thought it would be common sense.

It is. But when the operator decides ...for whatever his reason... to leave the engine running, then climbing up the motor is not an acceptable option, and you have to get back onboard some other way. If there's no ladder (and no crane), that only leaves climbing in over the sideboard.

Now you've already admitted that your "leg throwover" isn't suitable for inflatable Zodiaks. Its also not going to be suitable for non-small high-sideboard diveboats, such as this one: http://www.bequiadiveadventures.com/images/diveboatnew.jpg (FYI, this is the Bequia diveboat that the gal with the snorkel problems and I were waiting to reboard).

Bottom line is that there are times where the gear must pragmatically be taken off in the water and handed up, even if our personal preferences are otherwise. This is where a QD can be of benefit.

Oh, fer cryin' out loud, -hh... Where do you get this stuff? Are you just sitting around making it up? Don't take off your BC UNDER the boat. Give yourself a little room... You should anyway. Working a QD close to the boat is just as dangerous as dunking out of a bp/wing close to the boat. The answer isn't to use a QD... The answer is to not be so close to the boat.

Sure, you don't want to take your gear off while on top of the diveboat, but the reality is that you can't get back onboard a boat without at some point getting "close" to it.

And anytime that you get near a boat, there is a risk of getting hit by it. In fair winds/weather, this risk is negligible and its not a big deal to turn your back to the boat for a moment or even a few minutes. It is when conditions aren't ideal that a boat can move surprizingly quickly and the risk of a diver getting blindsided and whacked the highest.

Now I never suggested that a QD was a tool that lets you get _closer_ to a boat before getting out of your gear for an exit of this type...my point is that a QD is useful because it helps an attentive diver to keep a better eye on the movement of the diveboat during the process of removing gear, which can prevent getting hurt by the boat *if* the boat does not behave as expected. This assumes that the conditions are sufficiently non-ideal such that there is a meaningful risk from the boat to worry about.

Now since you hyperbolicly suggested not being "under" the boat while removing a BC (for those situations), but this begs the question of what you consider to be the optimum standoff distance for all circumstances? Is it 5ft? 10ft? Make a suggestion. You may disagree, but IMO, the proper standoff varies with and depends upon the specific circumstances.

...Or better yet... Don't remove your gear before climbing into the boat. Exit while wearing it, just like everyone else.

The unfortunate facts are that not everyone at all dive destinations do it as you suggest, even if this represents 100% of your lifetime experience.

For example, on the Wave Dancer liveboard in the Galapagos, they use inflatable Zodiaks (which you've already admitted you can't do a "leg up" on), and they keep the outboards running (no "climb the motor"). Where do I get this? I was in the Galapagos for two weeks last November/December, including a week diving onboard this liveaboard.

My PC's 35mm slide scanner has been down, so I've not been able to scan in many of my UW slides, but I shoot print film on land, and my flatbed scanner is up: here's some of the topside life: http://tinyurl.com/m812

Similarly, the boat used by Bequia Dive Adventures (photo above) with the "too high" sideboard, and they kept their dual outboards running. Exit was to hand gear up, then climb a really frail temporary ladder. Where do I get this? I was onboard this diveboat for a full week this past May.

Even idle moored diveboats with stern ladders can sometimes be problemmatic: ever see the entire 5ft length of a large diveboat's stern ladder pull clear of the water on each wave and come crashing back down like a Guillotine? I have. Reboarding the boat on that day was not fun, and separating gear from divers made it a less dangerous task for some of them (particularly the less skilled or physically small). I'll let you know if anything unusual happens on these boats when I get back from two weeks Cayman Brac later this fall...are you sure you don't want to come along? Here's a photo of the diveboat and the wind/seas from last September: http://tinyurl.com/m828. Oddly enough, diving was cancelled on this day...some minor problem with 80mph winds gusting higher as Hurricane Lily passed directly overhead.

Sometimes, conditions merit separating ~40lbs of gear from the diver and hauling it onboard separately, and sometimes they don't.

...So I pose to you, -hh... When was the last time you took a DIR course?

You apparently assume that I'm not familiar with their materials. In 2001, I was contacted by a DIR Rep and asked if I was interested in critiquing the content of their DIR3 training tape prior to its final editing and public release, which I was more than happy to do for them. Overall, DIR has some very good stuff, but it must be viewed in context of their assumptions as well.

For example, explain in dive theory terms the underlying rationale for the specific gas percengages they selected for their "TriOx" mix.


-hh

 

[SeaJay]

-hh once bubbled...


It is. But when the operator decides ...for whatever his reason... to leave the engine running, then climbing up the motor is not an acceptable option, and you have to get back onboard some other way. If there's no ladder (and no crane), that only leaves climbing in over the sideboard.

Now you've already admitted that your "leg throwover" isn't suitable for inflatable Zodiaks. Its also not going to be suitable for non-small high-sideboard diveboats, such as this one: http://www.bequiadiveadventures.com/images/diveboatnew.jpg (FYI, this is the Bequia diveboat that the gal with the snorkel problems and I were waiting to reboard).

Good looking boat.

Do you mean to tell me that the operators did not provide you with a ladder for exiting? How did they expect you to exit? How did you exit?

Bottom line is that there are times where the gear must pragmatically be taken off in the water and handed up, even if our personal preferences are otherwise. This is where a QD can be of benefit.

I don't agree. If your gear must be removed (which I don't believe to be the best option) then I believe it to be easier to flip one buckle and duck out of your gear than to disconnect a myriad of QD's. At best, they're both viable options and the QD's are unnecessary. And if they're unnecessary, yet a potential failure point, why have them?

Sure, you don't want to take your gear off while on top of the diveboat, but the reality is that you can't get back onboard a boat without at some point getting "close" to it.

Of course. Since your example includes gear removal, I recommend getting maybe 20' from the boat and removing your gear, then swimming in and exiting safely. I don't see how having QD's has any effect whatsoever on safety during this procedure.

And anytime that you get near a boat, there is a risk of getting hit by it. In fair winds/weather, this risk is negligible and its not a big deal to turn your back to the boat for a moment or even a few minutes. It is when conditions aren't ideal that a boat can move surprizingly quickly and the risk of a diver getting blindsided and whacked the highest.

...So you're claiming that a boat full of people and gear, with the motor off, even on rough seas, is suddenly going to swing sideways or backwards (exit point) and run over a diver? If that's the case, how would you handle that, even if your eyes were looking at the boat at the time? I mean, there you are, on the surface, with your gear off, and you're wearing a buoyant wetsuit and holding your BC...

Now I never suggested that a QD was a tool that lets you get _closer_ to a boat before getting out of your gear for an exit of this type...my point is that a QD is useful because it helps an attentive diver to keep a better eye on the movement of the diveboat during the process of removing gear, which can prevent getting hurt by the boat *if* the boat does not behave as expected. This assumes that the conditions are sufficiently non-ideal such that there is a meaningful risk from the boat to worry about.

Well, I'm suggesting that there's a better solution to whatever problem you're describing than using a plastic connector, which is prone to damage from errant tanks, careless crew members, and the like.

Would you use a plastic connector on your parachute harness? Would you be interested in a "quick disconnect" on there? I don't see losing your life support underwater as any more of a palitable option. Why would you want a qucik disconnect, when there's no issue in taking the gear off in the first place?

Now since you hyperbolicly suggested not being "under" the boat while removing a BC (for those situations), but this begs the question of what you consider to be the optimum standoff distance for all circumstances? Is it 5ft? 10ft? Make a suggestion.

Okay. 20 feet. I wouldn't get any closer to a hull in serious seas... Give yourself some room and keep you and your rig buoyant. Swim it in when it's your turn to exit.

Of course, I wouldn't remove my gear in the first place... I'd stand off around 20' in the first place, waiting for my turn to exit. When it was time, I would exit. Simple.

You may disagree, but IMO, the proper standoff varies with and depends upon the specific circumstances.

Sure, man... You can get closer if the conditions are better. Why take something so simple and make it so hard?

The unfortunate facts are that not everyone at all dive destinations do it as you suggest, even if this represents 100% of your lifetime experience.

Of course they don't, and of course it's not been 100% of my lifetime experience.

The people I choose to dive with exit wearing their gear because it's the simplest and safest method.

Hey, if you want to remove your life support while you're in the water, feel free.

As far as I'm concerned, it stays on me as much as possible, and I like to exit wearing it when I can, which is almost always.

For example, on the Wave Dancer liveboard in the Galapagos, they use inflatable Zodiaks (which you've already admitted you can't do a "leg up" on), and they keep the outboards running (no "climb the motor"). Where do I get this? I was in the Galapagos for two weeks last November/December, including a week diving onboard this liveaboard.

Okay. How did you exit the water?

If gear removal was my only option, then I would have ducked out of my gear and exited like you did... No QD necessary. Of course, I believe there was a better option... Like not having a motor running while I'm trying to board the boat. There's hot water, 2-stroke smoke, and all sorts of nasties coming off of that thing. I also believe that while in the water, the pilot should be focused on me, not on a motor... Which would be better off left off while I'm exiting.

...So I'm to understand that the net "fix" to the unsafe (and inconvienient) method of exit, which includes an attempt to exit the water - into a boat in heavy seas - with the motor running - with no point of exit, such as a ladder - with sides that are too high or thick to roll into - is to have a QD on your BC? Do you not see that this is not a solution to the problem?

Similarly, the boat used by Bequia Dive Adventures (photo above) with the "too high" sideboard, and they kept their dual outboards running. Exit was to hand gear up, then climb a really frail temporary ladder. Where do I get this? I was onboard this diveboat for a full week this past May.

Well, I wouldn't have been happy about that situation... But I wouldn't have thumbed the dive for it. Frankly, I'm not real keen on having other people handle my life support anyway.

...But like I said, I'd have not called the dive for it. Like you, I'd have handed up my gear and exited on the "frail, temporary" ladder. I'd have asked the pilot to shut the engines off when I'm exiting, though, at least to avoid the exhaust fumes.

...Anyway, to remove my gear I'd have unbuckled my SS buckle and ducked out of my bp/wing... Then handed it to the crew and exited. I still don't see how your QD is a solution for a problem.

...And frankly, I'm not a fan of a solution for a problem that doesn't exist.

Even idle moored diveboats with stern ladders can sometimes be problemmatic: ever see the entire 5ft length of a large diveboat's stern ladder pull clear of the water on each wave and come crashing back down like a Guillotine? I have.

Sure, man... Me too. I don't see how a QD is a solution for it, though... And I certainly would avoid ditching my gear in heavy seas like that.

Reboarding the boat on that day was not fun, and separating gear from divers made it a less dangerous task for some of them (particularly the less skilled or physically small).

Hm. Well... If that's their chosen method for whatever reason, then so be it. I still don't see the necessity for a QD... Although if you want to use one, that's your decision.

I'll let you know if anything unusual happens on these boats when I get back from two weeks Cayman Brac later this fall...are you sure you don't want to come along?

Well, that's flattering. I appreciate the offer. Yes, I do want to come along, unfortunately, I have pressing things here at work which can't wait.

Sometimes, conditions merit separating ~40lbs of gear from the diver and hauling it onboard separately, and sometimes they don't.

Agreed. I question diving in those conditions which merit it, though... Or at least question the use of a small boat with no reliable exit point during those conditions.

But even then, I still do not see the need for QD's, and instead only see them as a detriment.

You apparently assume that I'm not familiar with their materials. In 2001, I was contacted by a DIR Rep and asked if I was interested in critiquing the content of their DIR3 training tape prior to its final editing and public release, which I was more than happy to do for them. Overall, DIR has some very good stuff, but it must be viewed in context of their assumptions as well.

Who called you to critique it? Have you taken any GUE courses?

For example, explain in dive theory terms the underlying rationale for the specific gas percengages they selected for their "TriOx" mix.


-hh

I'm afraid I can't... Or actually, I could, but would be afraid of distributing incorrect information. I have not been trained on that gas yet.

Being aware of your limitations - especially those in your training - is a tenant of DIR that I regard highly.

 

[-hh]

SeaJay once bubbled...


Good looking boat.

Do you mean to tell me that the operators did not provide you with a ladder for exiting? How did they expect you to exit? How did you exit?

I've been on better. As mentioned, there was a ladder, the "frail" one. It was deployed off of the port side, about 1m forward of the stern.

If your gear must be removed (which I don't believe to be the best option) then I believe it to be easier to flip one buckle and duck out of your gear than to disconnect a myriad of QD's. At best, they're both viable options and the QD's are unnecessary. And if they're unnecessary, yet a potential failure point, why have them?

Some of my BC's have/had them, and I've tried doffing gear both with and without using the QD's. The procedure that I've found that works best for me (if the gear is to be doffed in the water) is to pop the waist buckle, and then just one QD...the left shoulder.

I pop the left becuase I'm a righty. For someone who's a lefty, I'd suspect that they would want to pop the right shoulder QD instead. There is no compelling reason IMO to pop both.

Of course. Since your example includes gear removal, I recommend getting maybe 20' from the boat and removing your gear, then swimming in and exiting safely. I don't see how having QD's has any effect whatsoever on safety during this procedure.

Perhaps it comes from me carrying an UW camera and needing to first approach the boat to hand this up. As such, its unrealistic to then purposefully back 20ft away to get out of the BC...overall, I'd say that pragmatically I'd move 6-12ft away, depending on conditions, and preferably down the tag line.

...So you're claiming that a boat full of people and gear, with the motor off, even on rough seas, is suddenly going to swing sideways or backwards (exit point) and run over a diver?

It is "sudden" for some people because they don't bother to watch how the boat is tailing on the surface before they approach. Some divers will do their stop right under the boat and not notice all of this surface action. Even if you have watched, they can nevertheless still sometimes catch you offguard - - its a lot like watching wave sets for timing a shore dive entry/exit in surf.

And insofar as running over divers, I've seen moored diveboats tail distances greater than 20ft each direction ... deeper moorings are generally larger in magnitude. Wind direction vs. current direction vs. seas direction are also factors, as well as the magnitudes of each. Forward and back motion usually comes from stiff winds and larger seas...this "surging" is usually a foot further than you thought you could reach, or a foot closer than you want (eek!)

If that's the case, how would you handle that, even if your eyes were looking at the boat at the time? I mean, there you are, on the surface, with your gear off, and you're wearing a buoyant wetsuit and holding your BC...

If you have time/distance, roll back and kick away, and/or get a leg up and push off.

If not, reach out to the hull with your free hand as it approaches. Use your hand to both cushion the impact and to hold/push off. If the boat is moored, there will be a current that will drag you down the hull towards the stern. Solution is multiple small pushings off - - keep yourself close enough so that you can use the hull for a big push in an emergency, as well as to prevent too much of a velocity difference between the two of you - - the boat will drift by and you'll either make it to the end of the boat or the tailing will subside and the boat will move away from you (until its next swing).

IMO, its generally not a good idea to vent the BC and dip under the boat. First, you don't generally have the time to thusly react and second, you've already surfaced with some Nitrogen onloading and could dip down further than intended.

Well, I'm suggesting that there's a better solution to whatever problem you're describing than using a plastic connector, which is prone to damage from errant tanks, careless crew members, and the like.

And yet in over 20 years of diving with gear with plastic components, the total number of failures and breaks I've suffered add up to zero...no, wait, one: I broke off a plastic zipper tab on a ~5 seasons old 3mm SSA wetsuit in Destin, FL ~3 years ago.

Would you use a plastic connector on your parachute harness?

Technically, Nylon is also a "plastic" (a manmade synthesis from an organic aeromatic base, specifically sodium hydride, N-acetylcaprolactam, and polyoxyethylene)...so why is it that we have no problem with yards of "plastic" in the webbing of our dive gear?

It really depends on which plastic you're suggesting using. For some of them yes, and some of them no. I'm a metals traditionalist too, but when properly engineered, composite "plastics" can have superior tensile, toughness, and corrosion properties...simultaneously. For the most part, it just takes adding some chopped up glass fibers to the mix. Don't forget that we've been making gun parts out of "plastics" for decades, and there's even been composite reenforced rifle barrel that's been around for ~6 years, and its stronger and yet ~1/3rd the weight of a steel barrel.

Okay. How did you exit the water?

As previously expounded, it was "strip, dip and kick".

Of course, I believe there was a better option... Like not having a motor running while I'm trying to board the boat.

Yes, but these were "Third World" outboards that sometimes took them a half hour to get started in the morning. Their SOP was generally not to even untie the Zodiak from the mother ship until its motor was running, and they then left it running until it returned to the mother ship and tied back up. And given how close we were often operating near rocks and cliffs (often <20ft), not shutting them down wasn't such a bad idea.

...So I'm to understand that the net "fix" to the unsafe (and inconvienient) method of exit, which includes an attempt to exit the water - into a boat in heavy seas - with the motor running - with no point of exit, such as a ladder - with sides that are too high or thick to roll into - is to have a QD on your BC? Do you not see that this is not a solution to the problem?

The QD is merely trading-off different system risks. If you find that trade-off unacceptable, then don't make it. In this circumstance of diving off of zodiaks with running engines, if you're not willing to dive under these conditions, then don't go to these destinations..

The Galapagos liveaboards are one such destination. I'd suspect that Cocos is probably another, as well as any operation that is operating in remote enough areas such that they equip every diver with his own private EPRIB to carry.

I'd have asked the pilot to shut the engines off when I'm exiting, though, at least to avoid the exhaust fumes.

Hope you speak very fluent spanish. Its always funny hearing such a remark come from a smoker. By any chance, are you?

I'm not a fan of a solution for a problem that doesn't exist.

Nor am I. But consider the following: if we say that the risk of bobbing on the surface is unacceptably high because of head injuries and the like, what can be done to minimize that risk?

One answer is to give the diver a helmet. Another is to provide the diver a better Situational Awareness while he's on the surface. And so on.

If a QD can eliminate the need for the diver to ever dunk his head (thereby temporarily blocking his surface vision) if he has to take off his gear, does this not improve his Situational Awareness?

RE: TriOx

I'm afraid I can't... Or actually, I could, but would be afraid of distributing incorrect information. I have not been trained on that gas yet.

The percentages are not optimized for minimized ongassing for their designed operating depth as you would have expected, but are instead designed to match up to the "sum to 120" ongassing rule. The primary benefit of the mix is a toss-up between a reduced O2 clock (a good thing), the bragging rights of using "Mix" (a bad thing), and the extra cash that goes to the blending station for the fill (good or bad, depending on if you're the gas seller or the gas buyer).


-hh