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

by James Thornton-Allan

Based in Montgomery NY. and founded in 1991, Ocean Management Systems Inc., commonly known as OMS (www.omsdive.com) is revolutionizing the future of sport and technical diving through the implementation of today’s most advanced technology. The company is leading the dive industry with innovative life support, computer and analytical products that greatly enhance the diver’s situational awareness and safety during every phase of dive. OMS Inc. has built its core business, around neutrally buoyant steel cylinders, patented BC’s and backplate harness systems. These and other OMS products are typically known throughout the dive industry for their innovative design, and robustness.

The ‘Workhorse’ unbalanced regulator has been the standard in SCUBA diving for years. Why? Its rugged, simplistic, dependable, low cost design lends itself for use as a primary, recreational, technical and DECO regulator. This regulator in fact was utilized by the National Park Service as a primary SCUBA regulator
in its 190+ foot dive to the B-29 bomber in Lake Mead! The Workhorse now comes standard with (1) Black (installed) (1) Green (Nitrox) and (1) (Oxygen) Yellow cover.

Big Blue Tech. own four OMS ‘Workhorse’ regulator sets and use them solely for the 6m to surface ascent zone of accelerated decompression on 100 % oxygen. To deliver this review in a clear and fair manner, the review will be broken down into seperate areas of consideration.

Function:

The OMS ‘Workhorse’ is an unbalanced regulator which means the tank pressure has a considerable effect on the breathing resistance. This is not related to our review since we never took a breathe from it below 6m. With this regulator being unbalanced it also means its very easy to repair and service which is essential for this unit, - more on this topic in the section reliability and robustness that follows-. If you look at the picture below you can see how simple it is inside. When we compare the ‘Workhorse’ to other regulators we found the Scubapro MK2 almost identical inside.

Robustness:

The OMS ‘Workhorse’ is by far the most fragile and delicate of all our regulators. There is one major design flaw: the exhaust cover. The exhaust cover is a large piece of plastic covering the area where exhaled bubbles escape via channel openings on either side. This cover is also looped behind the mouthpeice and secures on to the rest of the regulator by 2 very small clips. Below you can see a comparison of this exhaust cover; one with and one without such clips.

While waiting for replacement parts, we used the mouthpiece to secure the exhaust cover on to the regulator with a strong cable tie. This doesn’t really help since the mouthpiece comes off very easily. In fact, the mouthpiece is always twisting in your mouth during decompression. You can see below how the second stage is assembled.

This problem became quite dangerous when the regulator comes apart in your mouth but you still have the mouthpeice where it should be. For trained and experience divers it’s not an issue, but it could prove very dangerous for novice divers. Being divers, we assume that having a regulator come apart in your mouth would certainly pose some concern to someone.

All of our regulators broke this way. Despite becoming increasingly aware of this issue and exercising caution during use of these regulators during decompression, they would still come apart.

Features:

One of the great things about this regulator are the interchangeable covers. This is a really nice feature when diving in a large team, allowing easy identification of the gas the other team divers are on. Identifying and differentiating instantly oxygen from nitrox, can prove to be handy in certain tech. diving situations. That would be the only unique feature about this regulator.

Reliable:

Building further on the issue of robustness, we also found the 1st stage of the ‘Workhorse’ to have a great tendency to leak after only 20-30 dives post service. Not a major leak, but a slow and steady trickle of bubbles tickling the divers chin (in technical diving, your oxygen cylinder is slung onto your chest; this oxygen cylinder being the one the OMS reg’s 1st stage in question is mounted on). When decompressing for 30 minutes it’s very aggravating and distracting. Additionally, getting parts in Thailand is somewhat difficult and we were unable to find available service schematics at the time of writing.

Testing Grounds:

We have taken these regulators from swamp bottom lakes to open ocean wrecks. We are certain we have been putting these regulators in the conditions they are designed for. As these regulators are secured by strap to the cylinder (for retrieval in the latter stages of the dive for decompression purposes), they are subject to impact with rock walls and boulders when penetrating caves and narrow overhangs. Furthermore, add to this the possible degrading effects of silt, sand and sun and ofcourse the occasional bashing about on busy dive boats during the kit up and storage process and one can understand why a regulator can fail mechanically at some point. However, given that these regulators are designed with such issues in mind, have a name like ‘Workhorse’ attached, and are produced by a company like OMS, one would imagine they could withstand these conditions (despite the stress or amount of repetitive diving strain placed upon them). During all dive testing and opinions formulated, the ‘Workhorse’ was only used at 6m.

Breathing:

It breathed fine at 6m, no worse or better than any other regulator we have used. Since it is a simple unbalanced regulator we imagine it would perform the same as any other entry level piston regulator.

Price:

One great feature of this regulator is the price tag attached to it. It’s cheaper than the competitors and when buying in bulk it makes a difference.

Conclusion:

If you’re thinking of buying a ‘Workhorse’ regulator, you have to consider primarily what environment you will be using it in and for what type of diving. If you’re using it for simple recreational diving where the regulator will be stored in a nice padded bag, you dive maybe once or twice a year and you live in the United States where spare parts are abundant and easily accessible; then this is a good regulator for you.

If you are considering of doing all the cool things advertised in the OMS catalogue then perhaps this is not the best option for you. If you are an avid recreational or technical diver with frequent dive exposure and you require a reliable strong regulator then you will find yourself dsappointed quite early on. For consistent performance - such as that required by a dive professional- we recommend the MK2 regulator with a R295 second stage (pictured above). We utilize these for dives to 40m and shallower and they prove to be very dependable indeed.

Yesterday was the completion of the local training for our DSAT Tec Deep student Hannah Lusby. From here on out it’s on to deeper waters where surface support is required to conduct this training safely. It’s fine to do beginner training on dive sites but without support the risk of an accident increases.

So on wednesday the 22nd of October we’ll dive the Unicorn Wreck aboard the MV Trident where we’ll use the comforts, support and crew to help conduct Hannah’s more difficult training in a safe and enjoyable manner.

Once that’s day is complete we’ll be off on the 3 day 3 night liveaboard to the HTMS (His Thai Majesty Service) Pangan to complete the course and do some experience dives.

Below are some images from diving yesterday at Chumphon Pinnacle.

In other news…unconfirmed… potential presidential nominee senator Barak Obama was key in helping the military come and identify the missing USS Lagarto back in 2005 because he was the senator of the state where the submarine came from. We couldn’t find anything on google.. mostly smear stuff about the election. If anyone knows a source for this story we would love to put it up.

BANGKOK, Thailand (4 Sep 2008) — Arrivals of foreign tourists in Thailand are down 30 percent, the Association of Thai Travel Agents said Thursday, blaming the drop on a state of emergency declared three days ago in the capital.

Bangkok’s international airport normally receives an average of 8,000 to 10,000 foreign visitors a day, the group’s president, Apichart Sankary, told reporters.

But arrivals now are 30 percent below average, he said.

“The political turmoil has badly affected the travel and tourism business in Thailand,” Apichart said, adding that 14 countries have issued warnings about travel here.

He said the fall-off in arrivals began after Prime Minister Samak Sundaravej declared a state of emergency in Bangkok on Tuesday following bloody clashes between rival activists that left one of Samak’s supporters dead.

The decline is already costing Thailand 400 million baht (11.7 million dollars) a day in lost revenue, Apichart said. On an average day, the country earns about 1.5 billion baht from tourism.

“Most of the foreign visitors are tourists who expect to have a good time in Thailand. If the government cannot resolve the problems properly and quickly, we may see a weaker future for the business,” he said.

Last weekend anti-government protesters calling for Samak’s resignation shuttered three key tourist airports for two days, stranding thousands of travellers. Rail services in southern Thailand have also been disrupted for a week.

Apichart said the closure of the airport in Phuket alone caused losses of about 750 million baht.

Tourism generates about six percent of the national economy, and Thailand had expected the industry to earn about 600 billion baht (17.5 billion dollars) this year.

But industry groups fear the ongoing protests could spark even more cancellations, just as the peak tourism season here begins in October.