First Dives Carl D. Bradley Stern

[john j]

Here's a description of what we did. I ask respectfully though, please don't turn this into a battle of DIR versus rebreather or whatever. They do what they do and we do what we do. I respect their system very much for OC diving and cannot argue with their safety record and accomplishments, but I have made other choices for my own diving.

We did 3 dives. Bottom times were 25, 25, and 23 minutes. They were definately not bounce dives. Next time I think we are going to stay down longer though. This is a huge ship and 25 minutes went by in no time. The descent time, including our leak check and final "OK" stop at 20 feet on the way down, took 5-7 minutes.

Gases used were trimix 10/70 for the travel mix and bottom mix, then air starting at 100 feet on the decompression and finally 100% O2 at the 20 and 15 foot stops. Rebreaters were set at 1.3 pO2. We took 5 minute "air breaks" by changing to a 0.7 pO2 every 20 minutes during the 20 and 15 foot deco stops. Max CNS exposure was just under 80% at the end of the longest dive. We dove based on VR3 computers, but also carried several different decompression tables, with various bailout situations, etc. in case of multiple computer failures.

For bailout, we each carried 80 cubic feet of 10/70 and 80 cubic feet of air, plus 25 additional cubic feet of 10/70 and 25 cubic feet of 100% O2 at all times during the dive. The 25 cubic foot cylinders also supplied the rebreater with oxygen and diluent, but the 10/70 diluent could be breathed via open circuit in a bailout situation if needed as well. In addition to all that, we staged 80 cubic feet of EAN 36 at 100 feet on the line and we had surface supplied oxygen set-up as an additional bailout option.

I carried 2 primary quality lights (one HID and one halogen) plus a third less powerful LED backup light. John S carried 2 primary quality lights (one HID and one halogen) plus 2 more HID lights on the video camera that could have been used to find our way back if everything else failed.

The very first thing we did upon reaching the wreck was to attach a powerful strobe to the line at the bottom. This was extremely helpful in finding our way back to the ascent line. I'll always use one from now on for these deep wrecks.

In our drysuits, we had electric heaters. John S had 50 watts of heating capacity and I had 60 watts. We had planned on placing extra heater batteries on the deco line, but found that the water was warm enough during the shallower deco stops that the additional batteries were not necessary, so we didn't use them. John S. didn't use his heater much, but I left mine on the whole time. I like being toasty warm.

Decompression time was just over 2 hours for the 25 minute BT dives and a bit less for the shorter dive. It was a very long hang indeed, but for some reason, I didn't get bored. The level of excitement was very high and on the bottom, the pucker factor (if you know what I mean) was somewhat elevated as well.

The dive was exciting, stressful, scary, fun, sad (when thinking of the loss of life of the crew) and lots of other emotions all wrapped up together. I liked it too becasue unlike my day to day life at work, etc, my actions had real and immediate concenquences. All of my decisions actually meant something and made a difference. I was so incredibly focused that it was almost like an escape from reality. Kind of like a super-relaxing vacation. All the unpaid bills, problems at work, family issues, etc. just faded away and I was completely immersed in the task at hand.

[Freedive WI]

Thanks John, that was the kind of info I was looking for.

I don't want to turn it into a DIR thing either. Although that's the way I choose to (scuba) dive, I still fine it interersting to see how you go about planning, and executing, these dives. Since you bottom times were so much longer than the OC guys, and you got photos on top of it, there must be something to it.

I also heard Greg mention that you were the most 'squared away' rebreather divers he's ever met- I guess this must be true or he wouldn't have taken you there. That's why I'd like hearing your take on planning vs. some of the other versions of bailout that I've heard of.

Maybe you can say a little about the vis and if you had enough to use scooters next time- that would be really cool for a wreck that big! My father-in-law has his video camera system mounted on his Gavin so that he can shoot video 'on the fly' while he zooms around the wreck. It would be neat to see something like that on the Bradley- if there's enough vis that is.

Jon

[ccuda]

John, you said it perfectly and I second that,

"I liked it too because unlike my day to day life at work, etc, my actions had real and immediate concenquences. All of my decisions actually meant something and made a difference. I was so incredibly focused that it was almost like an escape from reality. Kind of like a super-relaxing vacation. All the unpaid bills, problems at work, family issues, etc. just faded away and I was completely immersed in the task at hand."

...is why I think most of us love this sport of SCUBA so much!
It's what diving is all about, and the scenery we immerse ourselves into - whether it be wrecks, reefs, quarries, or the bottom of a pool, is eye-candy for the soul and the youth for the heart.


(Everyone needs to get out and dive more, hint: summer's almost over. Hey everyone, post less, dive more!)

[Freedive WI]

ccuda,

What you and John just said reminds me of a guy I that I used to teach scuba with. He was a lawyer by day and was looking for a sport to escape from the pressures of his job. He said that when he went skiing he spent the entire time on the chair lift thinking about cases. It was only when scuba diving that he could completely forget about work.

If you want to take it to the next level try freediving.

Jon

[ghosch]

John,

I read what you said about bailout gases carried, how did that work out from a standpoint of bailout capacity. i.e. did you both have adequete bailout to return to the surface unassisted, or was this a team bailout dive. I guess I could assume some SAC's and run the numbers, but I'm sure you already did that!

What software did you use to plan the dives and create backup tables and bailout plans?

[divbum]

I just quickly updated the web site with a short post from John and John and some of their photos. Needs a little work but, its friday and I am off diving till monday or tuesday =)

Safe Diving,
Greg

[divbum]

[quote='ghosch link' dateline='1091204184']
John,

I read what you said about bailout gases carried, how did that work out from a standpoint of bailout capacity. i.e. did you both have adequete bailout to return to the surface unassisted, or was this a team bailout dive. I guess I could assume some SAC's and run the numbers, but I'm sure you already did that!

Ghosch,
If you run the numbers you'll see in water the divers had enough gas to make without assitance (independently) to the surface with the tanks they carried and the bottles staged in water. If there was a triple lose of gas or more, I had on board enough gas to get both divers out of the water, from 200' and up. Which is as deep as my back gas was mixed for support. Satisticly there was plenty, but if you want to say what if's all day we can get to the point of not enough gas. But take in some major puker facter if ***t happended they would probably had to hit additional gas due to stress and incresed RMV. But they planned their dives exicuted them to the T, so the what if's are for another day.

What software did you use to plan the dives and create backup tables and bailout plans?
They dove their VR3's as mention earlier and I believe it was V plan, OC tables were cut on, but I might be wrong.


Time to go dive,
Greg[/quote]

[divbum]

Here is a link to the story in the paper this morning





Safe Diving,
Greg