300m dives achieved with what ?

[John C. Ratliff]

This is an interesting discussion, but I'm going to throw a bit of information out and see what comes of it.

First, about the original Calypso regulator that both Keller and Jacques Cousteau used. It has the exhalation diaphragm in the center of the LP diaphragm, and it was too small in diameter for U.S. Navy approval. So the U.S. Navy never used it, but the USAF did (I will soon post on Pararescue and SCUBA Diving thread about that). But it was a regulator breakthrough, and both U.S. Divers Company and AMF Voit produced it (the Voit Viking 40 regulator). I dived the Voit version of several years, and loved that regulator.

Now, I have not bought a new regulator in years and years. In part, that's because I collect old diving regulators, and rehab them for my diving. I learn their in's and out's, and figure out which one is the best. But it is also because I haven't found any current diving regulator that can beat the A.I.R. 1 regulator by Scubapro, and I still have two of those that I occasionally dive when circumstances are trying in the water (heavy current, with a lot of work). My look at current regulators is that you cannot get a larger exhaust opening than the A.I.R. 1 regulator provides, which is the whole demand diaphragm. The inhalation resistance is also virtually nill, and it is better than the Scubapro Pilot regulator, according to Scubapro. I have also run two first stages into the second stage, which no current production regulator has the ability to do. The U.S. Navy gave Scubapro an award for the Pilot regulator, and with the A.I.R. 1 it's successor, I don't think any regulator will ever beat it; may approach or tie it, but I doubt any would beat it...just my opinion, though.

Now, one last thought--the combination of the A.I.R. 1 second stage on a U.S. Divers Company UDS-1 is probably the best single scuba that was ever designed from a breathing standpoint. If I can get my UDS-1 going again, it will again be mated with the A.I.R. 1 regulator by Scubapro (still a problem getting those tanks hydroed, since they have a very huge, non-standard opening and need an eddie current test). But the UDS-1 valve openings and integrated first stage provided the best performance of any scuba I have ever used.

SeaRat

PS, the photo of me and Bob LeBarr of the Salem Aqua Club with our wolf eels and fish (sea bass and a ling cod) was taken in 1963, when I was using my AMF Voit Viking 40 regulator.

 

[Akimbo]

But taking today standards of WOB a side, I'm wondering what was the WOB from that regulator that used Keller in that dive, he probable wouln'd had survived the dive trying to breath from it diving with today tanks, probably would had tox out on CO2.

AFAIK nobody has tested any of the 1960s vintage regulators on an instrumented breathing machine to find out. Keller was using HeO2 as a bottom mix so DiveLab and NEDU are probably the only places in the US that are equipped to simulate that dive. I don't know how deep the Ansti breathing machines that diving regulator manufacturers have are rated for. This shows the breathing machine at Atomic Aquatics.

I don't think the old Calypso's WOB was bad enough to cause a CO2 blackout since Keller used it on the previous test dives. The Cousteau Constant Volume suit probably increased WOB more in the vertical position than the regulator.

 

[Akimbo]

It has the exhalation diaphragm in the center of the LP diaphragm, and it was too small in diameter for U.S. Navy approval. So the U.S. Navy never used it, but the USAF did...

I was thinking about this. I don't remember that the exhaust mushroom valves were any bigger on the few other single hose regulators on the market during that era... but you have several of them on hand to check. I "suspect" that water was harder to get out of the original Calypso and Viking 40 regulator housings though. I got one off E-bay a few years ago but haven't restored it.

AFAIK, the USN hadn't approved any single hose regulators for fleet use by the early 1970s. We had to get special approval to use single hoses on the Bathyscaph Trieste II because the floating film of AvGas made the corrugated hoses fail after a day or two.

 

[joe10540]

Who cares about the brand on the sticker? The guys that are setting records are probably not using off the shelf regs anyway. Sure they might start life as a production model but then the Mfg or the diver themselves gets in there and tweaks and polishes it so that it performs over what you could buy off the shelf anyway. Just like cars the badge on the outside has no bearing on what's under the hood. Upgrades and maintenance make or break performance in anything. Kirby Morgan is the only company I know of that will certify their out of the box regs to over 1000' and the commercial guys are going deeper with them than any OC record.

 

[Akimbo]

... The guys that are setting records are probably not using off the shelf regs anyway...

Maybe, but I'd be very skeptical. It doesn't take much to make an off-the-shelf regulator unstable. I've never heard of anyone with access to a breathing machine to see if their tweaks improved performance at depth or just made it chatter at different gas densities. Besides, WOB is pretty minor compared to packing enough gas, HPNS, decompression, and compression arthralgia.

 

[Centrals]

Late John Bennett was also using Apeks, believe to be FST, for his first adventure to 308m.
Was there any modification on the regs?
The boss of Capt'n Greggs Dive Resort in Puerto Galera should be able to answer that.

 

[John C. Ratliff]

I was thinking about this. I don't remember that the exhaust mushroom valves were any bigger on the few other single hose regulators on the market during that era... but you have several of them on hand to check. I "suspect" that water harder to get out of the original Calypso and Viking 40 regulator housings though. I got one off E-bay a few years ago but haven't restored it.

AFAIK, the USN hadn't approved any single hose regulators for fleet use by the early 1970s. We had to get special approval to use single hoses on the Bathyscaph Trieste II because the floating film of AvGas made the corrugated hoses fail after a day or two.

When I went through the U.S. Navy School for Underwater Swimmers in 1967, there were no single hose regulators that were Navy Approved. It wasn't until the Calypso III, and its Conshelf version that's any single hose regulator was approved. The MR-12 came at about the same time. All had enlarged exhalation valves. Buut the USAF was using the Calypso from day one.

SeaRat