On January 4th 2010 Big Blue Tech arrived at Rajjaprabha Dam on Chiew Lan Lake in Khao Sok National Park to head out towards the raft house which would accommodate use for the duration of the TDI Cavern Course and BSAC/TDI Compressor Operator Course. The course was taught by James Thornton-Allan for students Andy Cavell, Mark Slinn, Emily Billingham, Piotr (Peter) Paulo and Malgorzata (Margaret) Babiak

As the team arrived at the resort we set up the area for the compressor and charging of the torches and then it was time to head out to the diving area to start the skills of the course.. The course needed to be staggered to maintain a ratio of 4 to 1 for the instructor which meant James took Peter and Margaret for their first training dives while Emily, Andy and Mark practiced their buoyancy in fresh water with their technical diving gear. The buoyancy and control came naturally to Peter and Margaret who come from Poland where the majority of their diving experience is in freshwater, additionally both Peter and Margaret are diving professionals who own Asian Divers in Phucket. Peter himself is a PADI Course Director and a Tec Deep Instructor Training for PADI/DSAT. For all divers the skills which need to be performed with comfort include using a reel and line to run a continuos guidleline, propulsion and finning techniques, loss of visibility and primary flashlight / torch failure and various other skills to make the diver comfortable in this ovehead environment. Addition to these skills all diver require 2 sources of artificial light, to reels and 2 sources of air supply.

On the 5th Peter and Margaret completed their course and received their certification followed by Andy, Emily and Mark on the 6th.

For Andy, Emily and Mark these newly developed skills would be further put to use in the coming days of the expedition when we explore shipwrecks on the west coast of Thailand. The Advanced Wreck and Cavern skills are quite similar as they both illustrate the procedures for dealing with an overhead environment.

On the 7th of January the team heading off the lake after a few thrashings of rain where Mark commented “I started the day off with possible heat stroke and now I think I’m coming down with hypothermia!”, we loaded the truck and headed off to Khao Lak which would the our base for diving for the next week.

Gloucestershire based Severn (7) Shipbuilders has designed and developed an innovative rigid inflatable boat that is able to submerge and operate underwater.

Inflatable boat designed as underwater vehicleThe primary use of this form of vessel is for carrying maintenance workers and their equipment to undertake underwater repairs and routine maintenance of underwater structures, such as oil rigs, production platforms and bridge supporting structures.

The primarily operating profile would have the vessels launched from a surface maintenance vessel, where they will quickly travel on the surface to near the designated working area, and then completely submerge to operating depth using electric motors for propulsion and manoeuvring.

The outer tubes will normally be open, and can be closed with simple valves and vents. Contained within these tubes will be an inflatable inner tube that will only be inflated underwater to provide positive buoyancy for re-surfacing. An underneath compartment will contain the main fuel tank and powerful lightweight batteries. This will be capable of being flooded to assist submerging and to maintain stability underwater.

The crew will all be wearing scuba and breathing equipment, and will also be carrying the necessary tools and equipment necessary for the task in hand. All crew will be trained as helmsmen, and will be able to carry out any function in the use of the vessels at all stages of its operational profile.

Means of exit and egress: The vessel is designed to allow the occupants to easily enter and exit through the open canopy roof and is constructed entirely from marine grade aluminium, with standard transverse and longitudinal framing

Author:
Justin Cunningham