Archive for the ‘Technical Dives’ Category

Sidemount Rebreather Class in Gilboa Ohio

Friday, June 20th, 2014

This was a very busy week in June.   After packing the truck with five rebreathers, ten tanks, two drysuits, one wetsuit, camping gear clothes, sleeping bag and many spare parts, I headed out to Gilboa Quarry in Ohio.    The week included two classes; one a GEM Semi-closed sidemount class, and the other a full CCR sidemount rebreather class.

On arrival, half of the gear was unpacked and setup for the next days class.    The first class was SCR using the GEM Sidekick sidemount rebreather.  Balance, trim and proper buoyancy were some of the biggest issues.  The rebreather operation was not as much a concern as proper position and weighting for the best work of breathing.  I prefer to use an aluminum 80 for diluent / bailout.  However the students were more accustom to steel tanks which required more weight to counter balance.  We tried several different side mount harness during the class.  Each had pros and cons.  By the end of the class the divers were feeling much more confident and the buoyancy and trim were dialed in.

The next morning started the CCR Sidekick class.   After classroom work and gear configuration we hit the water for more trim and buoyancy work.   After a few dives and skills we were circling the quarry and starting our decompression dives.

On the next weekend we set up all of our rebreathers side by side to allow divers to go on demo dives.  Divers tried out several different units.  Others just stopped by to ask questions.   All in all a great week of classes and diving.

Intro To Technical Diving

Sunday, March 3rd, 2013

Diving season is around the corner, and we’re getting requests for classes.
Drop a line if you are interested.
DavidAOldham@gmail.com
609.226.0570
The TDI Intro to Tech course is the perfect course for divers who have heard about technical diving and want to find out more about this exciting branch of advanced recreational diving. This course walks students through the special techniques, planning procedures and skills that set technical diving apart from traditional sport diving. It will show them how to improve their dive planning methods, in-water skills and streamline their existing gear configuration, in a non-threatening and fun learning environment. The specific skills this course will highlight are:

  • Advanced Buoyancy Control
  • 
Gas Management
  • Situational Awareness
  • Trim
  • Gear Configuration and Selection
  • Many More!

TDI’s Intro to Tech course is a useful stand-alone course for the diver who wants to become a more skilled, more proficient diver regardless of if he intends to move on to technical diving. The course may also be used as an introduction to the TDI Advanced Nitrox course and the TDI Decompression Procedures course. And finally, it is also a good refresher for certified technical divers who may want to refresh their skills or have them re-evaluated by a TDI technical instructor.

CDT Fourcault promo

Wednesday, June 15th, 2011
CDT Fourcault

A while back, I spent some time on the CDT Fourcault diving shipwrecks of the North Sea. The trip was a blast, and I met some really wonderful divers. There were groups from Belgium, UK, USA, and Italy (actually only one diver from Italy). All were fine divers, and many great sea stories were told over the dinner table.

Since that time some of us have kept in touch, and exchanged photos and videos of the trip, and other dive events. The latest was a promotional video made for the vessel CDT Fourcault. There are clips from our trip, and even a shots of me.

Class Photos, Fall 2010

Wednesday, December 15th, 2010
Shooting a bag while maintaining buoyancy

Shooting a bag while maintaining buoyancy

This fall in the Northeast was a bad season for blowouts and poor visibility.  Several hurricanes passed by, stirring up the surf.  Often, this can help the conditions by mixing the surface water with the cooler water below the thermocline.  Unfortunately this fall it cleared out the plankton on the surface, then just stirred up the bottom into soup.  At this point, the surface had over 50 ft of visibility, but the bottom would drop to less than 5.  That’s on the days we could make it out.

On the plus side, this gave me the opportunity to drag some students up to Dutch and finish up classes.  Once most of the drills are done, I dragged the camera along to grab a few shots.   After this fall, I needed the practice or I’d forget how to work the housing.  Also, I’m playing with a new lenses/port combination that takes some getting use to.  For what it’s worth, here are some of the photos that came out well.

Count the Counter lungs

Tuesday, October 12th, 2010

A friend just asked an interesting question:  Why have two counter lungs vs one?

I must admit, that no one ever told me an answer to this question, but here is my reasoning for 2 vs 1:
One counter lung only lets the scrubber work during half of the breathing cycle.
If the lung is on the exhale side, then it inflates on exhale, but gas only passes through the scrubber on inhale.
If it’s on the inhale side, then gas passes through the scrubber only on the exhale.

If you have two counter lungs, half the gas passes through the scrubber as you exhale, and half passes through as you inhale. This makes the gas pass through the scrubber slower, (aka dwell time)  and therefore the scrubber is more effective.  I would also assume that the slower gas movement would decrease the work of breathing of the unit.