OMS and their Bungeed Wing

[Joe R.]

I'm new to this whole thing...so bare with me. I know you'l agree simple is best and streamlined things move better through the water. I learned a long time ago you don't knock someone elses geat selection...Once I was in a shop where the owner was always putting down 'new' customers equipment...the shop has long been closed. I will say this OMS makes a great LP tank. I think its the best. In fact if we did'nt have the equipment choices we do and intellectual growth in the tek community we'd still be diving double hoses.
I too take the dir ideas and apply whats best for my diving. Stay safe!

 

[Lost Yooper]

I challange anyone willing to poke a hole in their bungied wing BC at depth and see what happens (something not unlikely to occur in wreck diving). It will completely deflate, and you will not be able to inflate it. You'd best have well balanced rig (another DIR thing) if you plan on getting up (unless, of course, you have the massive double bladders to rely on ). A non bungied wing will not completely deflate. This is not a myth. If you don't believe me, go ahead and try the experiment.
I have tried and been around bungied wings, and I completely agree with most of the faults noted. That said, I wish everyone the best on their purchases, and I can regretably say that I too was in your shoes once. Maybe ya'll will figure it out someday . I've done my fair share of bad equipment purchases.

Take care.

Mike

 

[roakey]

Originally posted by NetDoc
have there been any actual flow tests done in an aqueous environment? Or is it just more theory that has been propagated as fact again?

Yes. No.

The WKPP did tons of testing. They scooter, so they’d configure in such-and-such a way and “race” two configurations. Then, when the differences were more and more subtle they’d do time trails. Scooter for an hour with a specific configuration and see how far you go. Change the configuration and scooter for another hour and see how far you go.

Note that this is not the “throw a diver in a boat’s prop wash”-type testing that OMS did, this is testing in the actual environment in the actual conditions that the equipment will be used for.

This is how the WKPP eliminated bungee wings from serious consideration as well as rejecting the configuration with stage bottles on either side, etc. The WKPP tweaks, and tweaks constantly. Moving from the old Halcyon rebreather to the RB80 was a huge jump in speed and therefore distance.

A 10fpm increase in speed translates to 1/5 of a mile more cave explored after an hour and a half, so that’s why the WKPP has spend so much time and effort wringing each and every fpm out of their configuration.

They also did some gross testing by videotaping divers scootering in a halocline and then analyzing the images in order to identify, isolate and reduce turbulence.

But you don’t scooter? Neither do I, but I can’t say I won’t ever, and if and when I do, I already have a configuration that’ll squeeze every fpm out of a scooter that’s possible. I purchase for my endgame configuration, not just for what I’m doing now. It’s cheaper in the long run.

The WKPP started by modifying OMS, DiveRite and SeaTec wings to make them as functional, hydrodynamic and effective as possible. Asking those companies to manufacture gear to their specifications fell on deaf ears, so Brownie’s Third Lung spun off a new company, “Halcyon” to manufacture technical gear to the WKPP’s specifications. OMS and DiveRite could do the same, and the fact that OMS is now offering wings without bungees is an indication that they’re at least starting to see the light. Still, if you buy an OMS wing you have to replace the LP and corrugated hoses with shorter ones to get rid of the danglies, allow the air to siphon out without difficulty and allow you to manage your buoyancy while dealing with dry suit inflation and/or clearing your ears.

Might as well buy a wing that’s correct form the get-go and not have to worry about replacing stuff on a brand-new product.

Of course all this tweaking for hydrodynamics pales when compared to the bungee “power leak” feature. That one datapoint is enough for me to completely rule out a bungied wing from the slightest consideration. And I don’t need the WKPP to tell me about that flaw.

Oh, but that’s right, OMS has a solution for that too! You can get *redundant* bladders and get more bulk, more complexity and more drag for more money! What a deal! The perfect lose-lose situation!

No thanks. The WKPP has done more testing than I could ever hope to do on my own, or any of us could hope to do. If it’s been proven over three miles back in a cave, it’s good enough for my weenie dives.

Roak

 

[Uncle Pug]

Has anyone on this board owned and dove with a Halcyon BP/harness/wing.....

And then gone to an OMS bungee????

Or Vise versa.....

If so.... I would like to hear about your choice/experience/conclusions....


When people have actually owned and dove both extensively....
And not just read sales liturature or testamonials....
Their opinion carries a little more weight....

 

[Joe R.]

Has anyone ever seen a tuna, whale or shark with bungees? Hmmm. Or are they extinct?

 

[roakey]

Originally posted by Uncle Pug
When people have actually owned and dove both extensively....
And not just read sales liturature or testamonials....
Their opinion carries a little more weight....

Dang, I guess I can't tell folks anymore that smoking's bad for them since I haven't been a smoker and an ex-smoker.

Some things are obvious. The power-leak feature is one I don't have to experience to know that it's a bad idea, just like I've never jumped off a cliff, but I know it's a bad idea.

On one hand we have OMS' marketing division publishing “prop wash” tests and on the other we have quantifiable testing by the WKPP.

The WKPP, Ok, George, wants to connect Wakulla to something else really, really bad so no one can ever break their record. If the OMS wings would get them further than the Halcyon wings, they'd be using them. They don't give a hoot whose equipment they use as long as it gets them as far as possible and back safely.

This is what the “marketing ploy” naysayers don't understand. Who makes the equipment isn't important to the WKPP, period. It's how it performs.

Roak

 

[Uncle Pug]

Originally posted by roakey
Dang, I guess I can't tell folks anymore that smoking's bad for them since I haven't been a smoker and an ex-smoker.

You can tell em....
It just won't be as impressive as that lady with the hole in her throat...

BTW... glad you're not dead!

 

[The Chairman]

But, the analytical in me just finds fault with BOTH methodologies. Not enough controls in either to warrant an unequivocal statement of fact. The prop wash don't wash, and the scooter runs out of steam too. I know that there is an hydrodynamic equivalent of the wind tunnel. There just has to be, and it is too bad that this gear is not subjected to real scientific methodologies.

Even if GI has no monetary stake in the Halcyon wings, I believe he has some professional credibility to "protect". It is not unusual for any tester to sub-consciously give an edge to the product he prefers. It's usually followed by an "I told you so!"

So maybe twixt the lot of us, we can calm down a bit and reason out a surefire method of quantifying the drag of a BC. It would be interesting to see how vest compares with wings and so forth. The results would have to be fair and reproducible. Should the BC be tested alone or with a diver. How much flow would we need? Could we replicate that flow with a spring (fairly consistent) and then measure the force pressing on the system?

As for the possibility of a catastrophic loss of air, well, even a stroke knows you should be able to ascend WITHOUT air in your BC. If not you are way over weighted. As for the added "bulk"... not on OMS... they use two bladders in the same shell. The shell is the limiting factor, not the bladder. More confusing??? Not anymore than adding any redundancy. You dive with two tanks, three valves, two regs, two masks, then why not two bladders?

In final retrospect, I would be hard pressed to give up my OMS IQ. I love it and it fits just soooooooo sweetly. If there was some real empirical data on the drag, I might consider getting rid of the bungees, but I do love the reduced shift in air when I change attitude in the water. No abrupt movements because all of the air went aft. It just works for me BUT... I think I will buy some Halcyon wings sometime after I finish my instructor's course. Then I will know for sure… at least for me! I would never presume to tell others that their gear is “no good”.

 

[Uncle Pug]

Originally posted by NetDoc
I would never presume to tell others that their gear is “no good”.

Uh huh....
Well, we'll just see about that....

Using the scooter to measure relative drag is the ultimate empirical test.

And how dare you tell us it is "no good" ?


winkers !!!

 

[roakey]

Originally posted by NetDoc
BuI know that there is an hydrodynamic equivalent of the wind tunnel.

There is. About 5 miles form where I'm sitting is the US Olympic Training Center's swimming ergo tank. It creates a zone with a fixed but settable velocity of smooth, turbulence-free water that keeps a swimmer stationary in front of a window so the coaches can analyze and improve our athlete's performance.

So if you want to ante up for the tank, be my guest. If you have to ask how much it costs per hour, you can't afford it.

If you're not about to ante up for the tank, we're left with OMS marketing department’s "prop wash" method or the real, live, as-it’s-to-be-used scooter testing done by the WKPP. Your choice.

Again, believe me, if an OMS wing got George 100 feet further in Wakulla, either he'd be using it or Halcyon would be emulating the OMS wing, not visa versa.

Roak