PADI Deep?

[Hobby]

Sorry,I've been away.I'm actually clearing things up as I'm now redundant once again and this is my last day in work,and hence on here etc.(No IT access at home).
 Daz's/Rob's desciption is obviously correct on this(I think that the method is also described in that Divernet link on twinverts).This is the benefit of the inverts(when one does so much knob twiddling!) As said I personaly prefer a contents guage too,as I also have no problem with not having to ascend with a third of my gas remaning.However it must be remembered that the rule of thirds was developed in exterme conditions where safety always came paramount.It was also adopted in sump applications etc.Another phrase I often heard used was,"A third in,a third out and a third in case."
Hobby.

[Seadart Bob]

<font color='#333399'>Hi Hobby
Ref RN rigs.
Only ones I used were SABA which were twins inverted, I think these are the ones you are referring to.
Normal air sets we used for SAR, also used by the fire service in the sixties and SDDE for the deeper dives.
The SABA’s were introduced around 1960 prior to that it was UBA sets  and Standard equipment. UBA sets were still in use well into the sixties by Clearance divers but SW divers transferred to the SABA’s
It’s been over 30 yrs since I have seen a SABA I expect it has been updated a number of times by now.
The set I remember was made up with two alloy cylinders 9lts per cylinder. [main and reserve]
Charged to 2400psi 152 ats rings a bell but not sure.
Navy uses ats not bars. The whole set is set into a lightweight frame, with arms that came over the shoulders and secured at the front by a weight pouch. A weight box is also set between the cylinders at the back and had a quick release wire running through the left shoulder arm.
Also set in the back was the manifold/reducer and demand valve at the top. The manifold comprised of 5 outlets 1. main cylinder valve 2. reserve cylinder inlet 3. pressure gauge 4 supply to the reducer and 5. charging connector.” note the pressure gauge was set at the back as well, only used for charging purposes”.
Next was the reducer. “Single stage high flow double compensated” remember having that drummed into me haven’t got a clue what it means, output was set at about 65psi sea level and relief set to go at 200 something psi.
At the top was the demand valve one side housed the tilt valve the other the exhaust chamber and of course your twin hoses leading off to you mouth assembly that was fitted into your full face mask.
Nose clips were the order of the day in those days. A big help if you had sticky ears and of course no bubbles in front of your mask.
Fully loaded it would weigh about 60-70lbs if using lead boots add another 24-28lbs.
The set is not designed for recreational diving, it’s robust and matlote proof this thing would be banging about on a ships hull while you were trying to work. so no dangglie bits hanging off it.
In the old days [swing that lamp-pull up another sand bag Paul] to put one diver in the water you would have on the surface: :- A diving officer. Divers attendant. A stand by diver. A stand by divers attendant.
And perhaps an odd bod to use as a gofer.[surface team no expense spared it was a big firm they could afford it].
The diver would be attached with a life line at all times. He would be given direction signals through his lifeline by means of tugs and pulls  [pulls and bells. as if ringing a ships bell] obviously a coded system was used.
A diver could also have a buddy but he  would be attach by a safety line from diver one who was attach to the surface. The same surface crew could cover for other teams of divers so it was not necessarily 4-5 crew to one diver.
After breathing down his main cylinder the diver would operate the reserve valve and equalize out the two bottles and then shut off the reserve valve. The diver using his right hand to operate the valve. Now he has two half tanks. He will continue using his main tank until empty, carry out the same procedure except this time leave his reserve valve open, he now has two quarter tanks. Time to signal the surface and come up 25% of your total air left in case of emergencies.
With all this support on the surface their was no need for  a contents gauge. No need for a watch. No need for a compass. No need for a computer[not invented anyway]No need for a depth gauge.
All those dangglie bits would help to restrict a diver anyway. Navy did not trust us with expensive bits of kit. It wasn’t till I went SAR that they gave me a watch.
Would you use it for recreational diving?
It was only suppose to be used to a depth of 60ft  but we used it to a 120 on a few occasions, spare set being tied off on the shot to do stops.[all stops controlled from the surface no need to carry tables]
With a bit of engineering it could be converted to take modern day tec but to be honest unless you were into diving relic equipment I wouldn’t bother.” I am” so yes I would dive with it you could only use it on none deco dives anyway. [that’s all I do these days, also solo so sod taking air for someone else]
Would get a bit uncomfortable across the shoulders if you were not wearing a padded under suit.
Suit inflation came from a small cylinder attached to your harness and screwed to a connector on the front of your suit, if you over filled , stick your fingers in your cuffs and let it out more often than not water came in as well use the same procedure for assent.[no dump valves in those days]
Yes the SABA was basic but it has stood the test of time brought into service over 40 yrs ago and still going if that’s what Mark  was looking at, at Horsea Diving Centre.
There  were  a number of different types of divers all using different types of kit the SABA is just one of them..
HTH and clears up a few points.
Cheers
Bob.
ps. do you have one of these old SABA's?

[Hobby]

Cheers for that Bob it's great!
The SABA is'nt the same as the one I have or indeed am familiar with.The one I have(and always known)is known to me as the Sabre set due to the manufacturer....similar though.....?
My rig(Sabre valves/,manifold,faber cylinders) consists of two ally7's(?),can't remember the WP at present.Inverted,only one din outlet on the mainfold,this I've seen either hooked up to Conshelfs(full face or seperate)and even an AGA full face.No contents guage,etc.There is just a simple backplate on this with webbing however,no attendant weight pouch etc.The set's quite new,been used about 3 times before a load were auctioned off(they actually got bought by a scrap mechant for the valves,I got one of 3 sets that escaped)
I did'nt think anyone still worked in ats anymore!
The sets as used by the RE dive teams when using scuba too,I think the kits been standardised across the board,same as seen here but without the toy guard valves etc(I think the Sabre stuff generally gets removed before selling them off!)
I see your point re.using the lifelines,surface crew etc.as you know this is still the norm in prof applications,hence my use of contents guage etc.I've also used them as independants but am now having a look at the single reg again.
Hobby.
Whops,it's like this:-
http:www.divernet.com/gear/invert1198.htm

All Enriched Air is Nitrox , but not all Nitrox is Enriched Air ; it can contain less than 21% oxygen.

Set your mind at ease John?

Keep it safe!

[Mr T.]

Whilst in Maldives last July, there was a Jock/Yank undergoing his PADI AOW course; part of which is the requirement to do a 'deep' dive to 30 metres.

He was a good lad, CFO for a section of the largest global drinks manufacturer, and came bounding off the Dhoni happy as a pig in when he'd been out to the complete the deep section of the course.

Chatting to him about this over a beer in the bar later, he let slip that he'd been on a 32% mix to do his deep dive!! (it was actually 33.2%, as I checked the 60 bar he had left in his 80-ally tin later with my Analaox unit).

Now unless training has changed in the years since I did my AOW, one of the key points of taking students down to 30m is to show them the effects and affects of narcosis on one's ability to undertake tasks, reason, remain calm and RECOGNISE the on-set of the condition so as to take preventitive measures to either counter or correct them!?

His dive, as I understand it, achieved none of the above (he actually managed to complete the repeat tasks at depth on mix quicker than when he'd done them at the surface!) and in no way allowed him to recognise the on-set of narcosis.

Has PADI changed the purpose and methodology of it AOW course, as I think giving students a 32 mix off the bat to complete the deep section of the course is both counter-productive and, in a way, 'cheating'?!

[Janos]

I guess it depends if you think O2 is narcotic or not. (I think it is).

Laters,
Janos

[Scuba1]

As stated in PADI standards. Any dive deeper than 18m is considered a deep dive. So....... if you obide by the standards, you can do the deep dive for the AOWD at a depth of 19m. When you do the speciality (deep diver ), that gives you the ticket to go to 40m, you can do exactly the same thing. However you can not conduct a trainig dive deeper then 30m. Sraight out of " GSP". Sticking to the stgandars one can certify a diver to go to 40m, when in real life he has never been deeper then 18.5. Not clever,but that is what it states in the instructor manual.


Regards
MIchael

[scubadoguk]

Originally Posted by Mr T.

Has PADI changed the purpose and methodology of it AOW course, as I think giving students a 32 mix off the bat to complete the deep section of the course is both counter-productive and, in a way, 'cheating'?!

Maybe he was doing his nitrox cert at the same time as his advanced open water.
PADI is one of the few agency's that require dives as part of the nitrox course, maybe this was part of the reason for the nitrox, I would not let a diver use nitrox at that depth till they have done the class portion of the full course, but thats me.

[Mr T.]

Originally Posted by Janos

I guess it depends if you think O2 is narcotic or not. (I think it is).

Laters,
Janos

I think you might be missing the point here mate.

[detail]the diver had completed the Nitrox course earlier that week before doing his AOW course[/detail]

My understanding is that, as a key/non-selective module/dive of the course, AOW students are deliberately subjected to narcosis - on the deep dive module - so that they can recognise its symptoms and then redress it at depth (any depth) so that they might be safer divers themselves and, by extension, better support in times of possible need for their buddies?

What, then, is the use of removing, significantly, the element of exposure to narcosis by allowing the student to use a 32% Nitrox mix for the deep dive module of the course?

[gobfish1]

Originally Posted by Scuba1

As stated in PADI one can certify a diver to go to 40m, when in real life he has never been deeper then 18.5.

Regards
MIchael

Now thats how you sell a course.

Steve G