Inspiration Mod 1 - The worlds longest rebreather course. January 28, 2007
Posted by onthetrain in : Scuba Diving , trackbackDuring the past couple of years I have been gradually extending my diving depths, completing IANTD Normoxic Trimix and full trimix courses. As someone who researches things thoroughly and is confident with his skill set I had taken these courses pretty much in my stride.
I had done a lot of twinset diving in the 45 metre range and was comfortable and confident so the transition to helium based mixes was fairly painless.
As the year went on I came to the realisation that the gas logistics involved in deeper diving was a pain and I started to toy with the idea of buying a Closed Circuit Rebreather. After all I had not bought any expensive dive equipment for months and my wife was beginning to get a little complacent.
My unit preference was Delta P’s Ourobouros. I’ve used their dive computer for a couple of years and found it very reliable, a lot of people swear by the units excellent engineering and the company is just round the corner for me, so it seemed an obvious choice. The only sticking point was the cost! At his point it was definitly out of my range. I looked at all the mainstream units but my mind was made up in early October when a friend decided to make the move from a classic inspiration to an evolution and was selling his classic. I decided to buy his unit and do a year or two on it to see how it fitted my needs and perhaps moving to an ourobouros at a later stage. It seemed an ideal solution as I knew the owner had a couple of years problem free diving on the unit.
The first weekend in November saw me doing a weekends diving in Plymouth buddying Terry diving a unit I knew would be mine the next day. It was a perfect weekend, great diving and Terry had no problems at all with the unit. On Sunday afternoon I headed home to Poole with the unit in the back of my car. The last thing Terry said as I drove away was ‘let me know if you have any problems at all’. Words that were to come back and haunt him!
I’m sure most people will agree that in diving, especially more advanced diving, the most importnat thing you can do is to ensure that you choose your instructor with care. This was easy for me. I had done my trimix courses with Al Wright of MV Salutay, a long standing IANTD Instructor who had been diving rebreathers since 1998 and who had many years of experience on the Inspiration. I liked Al’s teaching style, thorough, progressive, practical but relaxed, small steps never too much at once. The fact that AL had recently moved to Poole and now lived just round the corner from me helped too. This meant we were able to plan to do the course in a way that suited me, over a couple of weekends with a couple of swimming pool sessions on my club nights in between.
We started the practical aspects of the course on 14 November with a practical session on assembling the unit, filling the stack etc followed by a session in the pool. In retrospect it was at this point that I began to suspect all was not well with the unit. On doing my predive checks the master controller switched off and the slave kicked in. The first controller seemed ok as a slave so we put it down to a battery problem. That evening we changed out the batteries and all seemed fine.
Saturday 17th November saw us at Vobster Quay in Somerset for the first Open water dives on the unit. I was very excited if somewhat apprehensive. I had heard all sort of stories about people having bouyancy problems when moving to CCR and I was not too keen on the prospect of making an ass of myself.
As we started to do the predive checks I could hear a hissing noise from the unit. Bizarre as it had held both positive and negative perfectly. A quick check reveled that the over pressure valve on the o2 first stage was blowing off gas. we stuck an interstage pressure guage on it and saw the interstage pressure was at 12 bar and creeping. It looked like our diving was going to have to be binned! A great start. Thankfully the day was saved by a very kind member of Vobster quay staff who leant us an o2 clean first stage.
During the diving I noticed that the readout on my vr3 from the fourth cell was going haywire. We put this down to a defective cell and flew the dive on fixed set point. All seemed normal with the handsets. during these first couple of dives we mainly concentrated on bouyancy, trim and OC bailout drills. I also go a plenty of practice at flying the unit manually. I must say that by the end of the day I was feeling good. My main concern was that I was hugely overweghted. We decided to shed the extra weight we had added aside from the trim weight. A great decision I felt so much more comfortable after that.
Midweek saw Al & I changing out the 4th cell and calibrating the VR3. All went well until we put the unit together to check everything and saw the dreaded message - Cell 1 failure, Cell 2 failure, Cell 3 failure. Having read the posts on rebreather world and elsewhere about cracked handsets I rang the previous owner to tell him about my tale of woe!
I must admit I was very impressed when Terry’s response was to tell me to get the head in the post to AP for checking and repair. He would contact Nicky and arrange to pay the bill. Top guy with total integrity and absolutely true to his word! Unfortunately though the head didnt come back until after I left for a two week holday in Sharm over Xmas so my palns to use this as an opportunity to get 20 - 30 hours on my unit were thwarted.
The unit came back whilst I was away so it was 13th before we were able to get back to try to finish the course. When setting up I had some problems getting good positive and negative tests so Al and I had had pulled the unit to bits searching for a leak and eventually found one on the ADV. We decided to change the o ring the next morning at Vobster . Once again disaster struck as when I tried to do this the ADV barrel rotated puncturing the diaphram! I also managed to sheer off the top cover of the over pressure valve on the exhale counter lung!
Cursed or what! I must admit at this point I really was ready to give up and go back to OC. It was only Al emphasising the positives of all the repairs to the unit that kept me going. I posted a plea for help on rebreather world and as a result I had some help sorting this out from Dave Thompson and at last it looked like I had a fully functional refurbished unit. I cant thank Dave enough for his act of kindness to a total stranger. Nice one Dave.
Sunday the 22nd saw me back at Vobster to complete 2 further dives. I was concerned that after so long away from the unit and with about25 open curcuit dives in between the first day might be a real struggle. Al, bless his heart suggested that I should just take it easy and get used to the unit again. In the event it went really well. Trim bouyancy and drills went really well as did firing my bag, stops at 6m on 1.3 etc. I confess I was very pleased with myself.
Al reckoned we just needed one more dive to put it all together so yesterday 27th January 2007 saw us back at Vobster for the last dive of the course.
Throughout the course I had felt my harness was a little loose andthat I was slightly feet down in my trim. On Friday evening I adjusted the harness, shortening the shoulder straps by a couple of inches. What a disaster. The unit sat far too high, pushed me head down, restricted my movement and placed my stage on an awkward position. All of this lead to a few bouyancy and trim problems though all my drills etc went very well. At the end of a 75 minute dive I was still feeling very much less than pleased with myself. I will confess it was with some trepidation that I sat down with Al for the final debrief.
Whilst Al had noticed the problems and felt that the final dive was probably my worst of the whole course, he had seen enough across the course to be more than happy that I was safe to dive the unit unsupervised and to start building my skills and experience.
So at last my course is complete. I have a little over 10 hours on the unit and my aim now is to get 20 hours at 20 meters before the end of March so that I am ready for the season to come. I gained an invaluable insight into the workings of the unit and all the things that can go wrong. I feel well set to continue my education as a novice rebreather diver.
As a footnote I would like to thank Al Wright for his endless patience and assistance through all of the problems we faced on this course. Big thanks also to Dave Thompson for his help in my hour of need and to the staff at Vobster for helping with a variety of things and for listening to me moaning.
Thanks Guys.
If you would like to do a course with Al Wright (and I recommend you do) he can be contacted through the MV Salutay website www.salutay.com
ATB Alan
Comments»
At last, Phew from me, finally my old unit is working fine at least you had these probs now and not at 50m.
Still not got the Evo yet but when I do I will be clocking up the hours like you will.
Congrats at last.
Tez
Cheers Tez,
I have insider info that says you new unit will be with you in a day or two :-). Its been paid for!!
Need a buddy to rack up the hours?
let me know!
Odin
Hi paul,
Definitly take you up on that mate. Will PM you my number and email addy’s.
Alan