Gearing up for Tek

[peterbj7]

Just one question. Why do you (and Gui/DIR) specify that a wing must not be bungeed?

 

[Blackwood]

Just one question. Why do you (and Gui/DIR) specify that a wing must not be bungeed?

I've never concerned myself much with that one (not many bungeed wings around here), but I would imagine:

1) no added value,
2) potential to trap gas,
3) may be a snag hazard

edit: here's a search result... not sure if it's supposedly a "GUE/DIR" perspective, but some of it makes sense:

Just some thoughts on OMS wings.

1. Bungee wings have elastic cord laced around the bladder to supposedly keep it tight and streamlined at all times. What actually occurs is that surface folds are created in the wing, which with the bungees themselves increase turbulent water flow over this surface and thus the diver's drag.
2. The fore and aft profile is also greater with the bungeed wings. (More drag, heavier exertion, CO2 loading, etc.)
3. The bungees are very good entanglement points that pose an entrapment hazard. The bungee can not be easily reached if they do become snagged.
4. The bungees also serve to hold the bladder close to the diver's center of gravity, which makes it easier to roll, but makes it more difficult to maintain a perfect prone attitude in water. The standard unrestrained wings will float upward against the side of your tanks, resulting in a greater applied moment which helps keep you in a horizontal position, which is generally the position of greatest function for the diver (certainly from a decompression perspective).
5. The bungees also create a slight positive pressure within the bladder at all times, which will act to forcefully dump the wing when you hit the deflate. This is a faster dumping than the standard wing, but if you have a valve or fitting failure your gas may be all inadvertently dumped - very dangerous in an emergency situation.
6. The positive pressure in the restrained wing also creates a lung loading problem when orally inflating - just one more thing to contribute to injury or DCS.
7. This positive pressure in the bladder complicates using the inflator as a tertiary backup regulator,
8. OMS provides buoyancy compensators with as much as one hundred pounds of lift (as advertised by the manufacturer). If a diver is using the correct tanks for his or her particular application (considering the buoyancy characteristics) and is correctly weighted, there is absolutely no need for this amount of buoyancy in any situation.
9. Bungee wings were developed in response to the perceived need for additional buoyancy to support excessively weighted divers. It is irresponsible to dive with weight that cannot be ditched in an emergency and the use of a gross displacement device is a mistaken compensation for an erroneous practice.
10. Cost more

A diver must "settle for nothing less than perfection. Those who do will discover on their own the value
of such effort. Those who do not will never understand what the others are talking about".

Brad

1. I don't agree that increased turbulence necessarily increases drag. It could very well have the opposite affect (to which a study of golf balls, baseballs, or Boundary Layer Theory in general will attest.)

4. First half: the lift vector has the same affect regardless of whether it comes from a wing close to your back, a wing taco'd over your tanks, or a rope attached to the surface. Second half: I highly doubt that being horizontal versus being vertical makes a lick of difference to decompression (unless the diver is 10 feet tall).

6&7. I imagine that's blown out of proportion.

The others seem reasonable, though.

 

[Doc Harry]

A second mortgage would make it easier to purchase your start-up gear.

It also helps to save on unnecessary expenses -- dump the wife and sell the kids.

 

[DA Aquamaster]

Bungeed wings:

1. potentially create more of an entanglement hazard.
2. will be more likely to deflate and deflate faster if punctured as the bungess increase the internal pressure.
3. are harder to orally inflate in the event of an inflator failure or OOA situation due to the pressure of the bungees.
4. can cause issues with gas trapping.

On the plus side, tweaking bungee pressure fore and aft in the wing can help with trim - but a properly designed wing does not need that kind of help, so it's a wash.

 

[DA Aquamaster]

A second mortgage would make it easier to purchase your start-up gear.

It also helps to save on unnecessary expenses -- dump the wife and sell the kids.

Doubles are heavy, keep the kids for future tank sherpas.

 

[jrankney1]

Thanks to everyone who has posted here. There are lots of great comments and suggestions from everyone. To summarize what has been said:
1. Get a good instructor
2. Read up (various books)
3. Dive-a lot!
4. Don't rush to buy equipment-
5. Keep it simple.

Did I miss anything? I'll be moving up to Lancaster, PA in the next couple of weeks and will likely do my initial Tec training there. Any suggestions on dive locations near there or recommendations for instructors in the area would also be appreciated.

 

[Indian Valley Scuba]

You are a quick study jrankney1!

Your post incorporates much of what I posted earlier - I am glad it was received so well.

For recommendations on training of all levels and interests, including technical, I strongly suggest...us!

Check out our website or our training catalog and see what we might be able to do for you!

 

[forthefunofit]

If you are looking into Tek diving, find a great instructor first. In the midwest, the name Greg Such of Shipwreck Adventures in Two Rivers, WI consistently comes up in coversations. He's been great to work with.

 

[Atomic_Diver]

I dive a Dive Rite Transpac and Classic Wing, and for regulator Atomic Aquatics T2x and Z2