The JJ CCR is taking over Mexico!!!!!
Some time ago I was lucky to have the possibility to do a cross over training to the JJ CCR. My Instructor was Sami who is teaching on the unit since quit some time and already performed some very deep dives in the cold mines of Finland.
We started off by taking the unit completely apart even the sensor harness and the solenoid as well as running through the functions of the Shearwater Predator. The first thing that comes to mind is SIMPLICITY. The unit is extremely easy dis- and assembled and I LOVE the possibility to open/clean the solenoid as well as to change the wiring of the cells with no tools out in the field. This makes the unit especially interesting for people that travel a lot or do projects in remote areas.
The Predator has the OLED display that I am already a big fan off due to my Liquivision X1 and same as the X1 the menu is so incredible easy that even a 5 year old could use it.
The unit is very solid built and due to the back mounted counter lungs is very clean in the front. It has a manual O2 button that can be swivelled around and therefore be used as an off board gas intake. With the metal stand you can easily park the unit even on uneven ground without having to constantly worry that it will tip over. The can is made in a way that almost any tank seize will fit and there would be also the possibility to dis-invert the cylinders if wanted!
Right after that we went to the Cenote Chikin Ha for some confined water training. Already gearing up was nice due to the back mounted counter lungs which makes it very similar to putting on a set of doubles (minus the weight of course =)
Under water the unit performed flawless and some of the things I liked right away was the work of breathing, the single hand set and how easy and fast it is to flush the unit.
We worked ourselves though the standard exercises including Hyperoxia, Hypercapnia and Hypoxia as well as Boom scenario and different computer settings and options. One thing that the JJ has that I like on any CCR is the possibility to perform a diluent flush while being off loop with no mayor changes in buoyancy.
Some of the things I didn’t like was first and foremost the very sensitive automatic diluent valve which basically fired each time I was lowering my head a little, although I have heard that this got corrected some time ago and there is the option to switch it off and use a manual add button (similar to the oxygen one) only. In my opinion diving with minimum loop volume is very important for good buoyancy control and steady PO2.
Also I felt the unit to be quit butt heavy even though I was diving in a dry suit which again though is the same with almost all units on the market. Other things that bothered me a little were the water trap on the exhale side which simply doesn’t keep the water in the lung when you are diving in a horizontal trim and the bail out valve that constantly free flows when you are on the surface which can easily be fixed with a shut off.
The next day we went down south of Tulum to dive Kaan Luum which was really cool and a great experience. We ran through all of the emergency drills while swimming around in this huge sinkhole in absolutely green water.
Thank you Sami again for a great course and some awesome dives!!!
After that I started a CCR cave crossover with Mia who came also with her JJ from Finland.
She did her Cave One last year with me on OC and now was back for more. We had an amazing five days full of incredible long cave dives filled with drills and exercises. This is definitely one of the most demanding courses we teach here and divers need to have their units fully under control if they want to use them here in the cave environment. Many of the local caves are shallow and due their no/low flow nature are filled with fine grained sediments which once disturbed can stay disbursed in the water column for hours. Diving these caves asks for a super streamlined gear configuration, precise buoyancy control, fine tuned propulsion techniques and expert skills in dealing with zero visibility situations. The key skill is to deal with potential problems without creating new ones while in the process.
It was definitely not a walk in the park but Mia was on top of her game and was very focused and concentrated through out the course and therefore successfully completed it which made me very proud!
Congrats Mia, good job!!!!
I hope to soon get some more JJ divers here for some more CCR cave diving fun.