TUSA Launches SAV-7 EVO2 DPV

I first came across TUSA scooters being dived 'in anger' (aka used for real) during Divetech's annual Inner Space rebreather event held in Grand Cayman.

Inner Space 2012, Rosemary E Lunn, Roz Lunn, Divetech, scuba diving in Grand Cayman, scooter sign, Nancy Easterbrook, The Underwater Marketing CompanyI was happily bimbling along the wreck of the USS Kittiwake when a rebreather diver whizzed past me. For a brief moment I couldn't work out how he was moving so fast. His hands were full of a quite large camera system and he wasn't appearing to fin at all. And then I spotted that his legs were almost akimbo. He was sitting on a bright yellow TUSA SAV-7 EVO scooter - rather like someone would straddle a horse - and this was efficiently driving him through the water.

TUSA has just launched the the latest iteration of their diver propulsion vehicle - the TUSA SAV-7 EVO2.

This scooter has a useful depth rating of 70 metres / 230 feet and features the patented 'Hands-Free Riding Saddle'. If you are not familiar with this DPV, this is a 'hands free' scooter. You navigate it by twisting and arching your body accordingly, leaving your hands free to take photographs or check your gauges and computer, hence the seat on both the EVO and EVO2 is quite important. Very loosely it could be compared to a Western saddle. A flange or flat raised pommel (incorporating a lifting handle) is located to the front and the rear of the saddle. Attached to the front plate of the saddle, below the flange, are two wing arms. One on each side of the plate. These are secured in place by a 'super knob', basically a large nut. To use the relevant wing, you unscrew the knob and swing the relevant arm out 90 degrees, before screwing home the knob again.

Inner Space 2012, TUSA SAV-7 EVO scooter, Jay Easterbrook, SAV-7 EVO2 DPV, Diver Propulsion Vehicle, diving scooter, scuba diving, Rosemary E Lunn, Roz Lunn, The Underwater Marketing CompanyHow does this work underwater? Just imagine the diver is lying horizontally face down with the DPV secured between their legs, as if they were sitting astride a bar stool. The wings are reminiscent of pillion foot pegs on a motorbike. However they are longer and there is no physical contact by the diver piloting the DPV, ie they are not lying on them. The wing is a handle for an additional diver to hold onto for towing purposes, or they are a means of attaching equipment to the DPV. Two holes have been cut into each wing, allowing you to clip or karabina off kit to the wing. When not in use, the wing(s) can be retracted and secured in place to provide better steamlining, as they lie on the front of the saddle plate. TUSA state that this DPV is capable of comfortably towing two divers, hence the two wings.

I can see this scooter being quite popular in resorts like the Maldives where the currents are famous (or infamous?) for their strength. Whilst it is possible to mitigate for hard currents by diving at specific tide times, using reef hooks and diving with the current, there are times where you just want to go and look at a particular coral head, or fully explore a wreck, and you cannot get there because you are unable to swim against the hard current, or you do not have the time or gas to do it. TUSA state that by using a DPV you can travel 3 / 4 faster than finning normally. Plus using a diver propulsion vehicle can decrease fatigue and reduce gas consumption therefore allowing the diver to go further and faster in a variety of conditions, extending their time in underwater.

So what has TUSA changed on this model? Three things: speed, range and runtime.

SAV-7 EVO2 DPV, diver propulsion vehicle, TUSA SAV-7 EVO scooter, XRay Magazine, X-Ray Magazine, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company, scuba diving magazine, underwater motorbikeThe design of the rotational speed adjustment function has been reviewed to make it quicker and more responsive, and the DPV is now capable of 4.5km / 2.8 mph compared to 4.2km / 2.6mp on the previous model.

TUSA has also substantially increased the range, torque and burn time by exchanging the Lead-acid battery for a high performing, long-lasting Lithium-Ion Battery (complete with an L.E.D Battery Life Indicator). The SAV-7Evo had a range of 4,200 metres / 2.6 miles with a burn time of 80 minutes. The Evo2's figures are quite impressive. A range of 7,200 metres / 4.5 miles with a burn time of 120 minutes. Available in black.

Here are the specifications:

Speed: 4.5 km / 2.8 mph
Depth Rating: 70 metres / 230 feet
Dimensions: Length 720mm x Width / Length 28.5″ x Width 13.5″
Surface Weight with Battery: 20.5kg / 45 lbs
Submerged Weight with Battery: 0.3kg / 0.5 lbs
Range in Open Water: 7,200 metres / 4.5miles
Run Time in Open Water: 120 minutes
Battery Type: Lithium-Ion
Speed Adjuster: Rotational Speed Control with Variable Pitch-Type Propeller (3-Step: slow, standard and fast)
Safety Device: Sensation Current Shut-Down Device, Water Leakage Sensor, and Water-Cooling Motor Deployment

With 23 Years Of Hindsight – Rigging Options For Diving

A recent post on a diving forum stated "sidemounting is just a fad".

New(er) divers to the sport could be forgiven for thinking this style of scuba diving is a recent phenomenon.

Cave Photography, Gavin Newman, Mike Thomas, Cave Diving Group, CDG 50th Anniversary, Wookey Hole, Drager Dolphin rebreather, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company
Two Brit Cave Divers marking the CDG's 50th Anniversary by diving Wookey Hole, June 1996 Photo Credit: Gavin Newman

Sidemounting was actually invented in the 1960s by the Brits. They were exploring sites such as Wookey Hole, Swildons Cave and other underground systems, and would often find 'the way on' was blocked by a submerged passageway called a sump. In order to explore further, these sumps needed to be navigated.

British sumps tend to be short, cramped, flooded passageways, therefore buoyancy is not an issue nor is the use of fins. Cavers just needed a means to be able to breath and (sometimes) see where they were pushing. The caver would attach a cylinder and regulator to their body using a robust belt that allowed the cylinder to be worn against the body. This 'English system' of cylinder rigging allowed the explorer to crawl through both dry and wet sections of cave and keep on pushing the system.

During the 1970s the 'English system' was adopted across the pond by Floridian cave divers. These cave systems tended to be properly flooded with the emphasis on diving to explore the cave. Buoyancy, trim and propulsion became an issue, hence cylinders were moved from the waist / thigh area, up towards the armpit and against the torso.  Once again, these divers made their own rigging system. However it wasn't until the mid 1990s that the first commercial sidemount diving system was manufactured by Dive Rite. This was designed by Lamar Hires, a renowned cave explorer and instructor. 

The following article by Michael Menduno is reprinted from the pioneering American journal for technical diving, aquaCORPS, V4, MIX, January-February 1992.

Though double (twinset) tanks and stage bottles are generally a requirement for most technical diving operations, diving sets vary significantly depending on the specific application and diving environment. Here’s a look at some of the more common methods of set rigging as practiced today in the “doubles community.”

Squeezing By - authored by Lamar Hires

Lamar Hires, Jared Hires, Lee Ann Hires, Bob Janowski, Michael Menduno, aquaCORPS Magazine, Dive Rite, sidemount diving, technical diving, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company, XRay Magazine
A Floridian sidemount rig from the early 1990's, before Dive Rite released their TransPac system Image Credit: Bob Janowski

Originally developed for the tight low visibility sump diving that is common in Europe, sidemounts allowed spelunkers to more easily transport single cylinders through a dry cave to the dive site. In North Florida, the use of sidemount techniques has allowed exploration into small silty areas that were once thought impassable and has opened up entire new cave systems that were simply inaccessible with back mounted doubles.

Sidemounts reduce the strain of carrying heavy doubles up steep inclines, lowering cylinders down into a hole, and making those long walks through the woods to the dive site. Cave systems known to be silty can now be penetrated without heavy silting. Sidemount configuration means wearing the cylinders on the hips instead of the back. The cylinders are fastened in the middle with a snap to a harness at the waist. The necks are clipped off at the armpit using bungee material (a bicycle inner tube is preferred) so that the cylinders are forced to lay parallel to the diver’s body. Adjustments are usually needed at first to insure a snug comfortable fit.

When diving with sidemounts, gas supplies must be balanced for adequate reserves throughout the dive. The regulator and SPG hoses no longer lay across the back and instead are clipped across the chest area. The management of these is critical for proper monitoring of gas supplies and switching regulators during the dive. Back-up and emergency equipment must be streamlined and tucked away to achieve the desired profile—no thicker than two cylinders that lay along the diver’s hips.

Clearly, sidemount diving is not for everyone because of the potential hazards that exist; low visibility, line traps and squeezes that seem to get smaller and smaller are only a few of the obstacles to be overcome. A diver must be totally comfortable in all these conditions before considering sidemount as an alternative. Suitably equipped, divers who are, can usually find a way to squeeze by.

China Cult - authored by Billy Deans 

Billy Deans, Joel Silverstein, Michael Menduno, aquaCORPS Magazine, SS Andrea Doria, Poseidon, doubles, twinset, technical diving, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company, XRay Magazine,
Technical diving pioneer and educator Billy Deans Image Credit: Joel Silverstein

Previously isolated from the underground and fellow wreckers to the south, the east coast wreck diving community evolved its own style of set rigging suitable for the cold dark waters of the north and the available technology. Still seen on the boats that work the Doria, Texas Tower, the Virginia and the San Diego, a typical east coast wreck diving set consists of a pair of double 80s or 95s (10.5 or 11.5 liter) or secured to a large capacity BCD jacket with a manifold system, or commonly two independent regulators, which are rotated throughout the dive.

A 40cf (5.5 liter) pony mounted between the doubles serves as a bailout, along with a handmade upreel (hemp rope wrapped around a forearm-length aluminum spindle). For the most part, stage bottles, typically air, are something divers leave tied off to the anchor line at 10ft (3m), and oxygen for decompression is still used sparingly, if at all.

Now with the advent of larger tanks, harness and manifold systems, improved decompression methods and mix technology, all that is changing. Today, a well-outfitted high tech wreck diver carries a pair of cold-filled Genesis 120s (14.5 liter) with DIN crossover manifold and valve protectors, shoulder mounted stage bottles, or ‘wing tanks’, containing decompression gas (EAN and or oxygen)—do you really want to bet your tissues on that cylinder clipped off to the anchor line? Harness, bag and back plate system, argon inflation system and of course an upreel.

The result? Wreck divers are staying down longer, getting more of that first class china, and most importantly are doing it safer. After all, when you come right down to it, the most valuable artifact that you’ll ever bring home is yourself.

To read the full article, click here

First Published: X-Ray MagazineMay 2015 Issue 66, Page 78

Are You An Ardent Muck Diver?

Can you spare 5 minutes to help Maarten Debrauwer with his PhD research?

Maarten Debrauwer, PhD research, Hairy Frogfish, Southeast Asia, cryptobenthic fauna, ‎frogfishes‬, ‎ghostpipe fish, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company, XRay Magazine, Eric Hanauer, Muck Diving, Scuba Diving, Rebreathers
Maarten is doing his PhD on cryptobenthic fauna - ‪#‎frogfishes‬,‪#‎ghostpipefishes‬ etc - in Southeast Asia. As part of his research he has a survey about these little critters. The survey investigates which species are most popular with ‪#‎divers‬ who are interested in muck diving.

Maarten Debrauwer, PhD research, Hairy Frogfish, Southeast Asia, cryptobenthic fauna, ‎frogfishes‬, ‎ghostpipe fish, Rosemary E Lunn, Roz Lunn, The Underwater Marketing Company, XRay Magazine, Eric Hanauer, Muck Diving, Scuba Diving, Rebreathers

It is part of a larger scientific research-project that investigates the ecology and threats of cryptic marine fauna in Southeast Asia. To better protect these species, it is crucial to know the key characteristics of muck dive tourism.

Muck diving is a distinct type of diving that mostly occurs over sand or mud areas, with little or no coral reef. The focus of muck diving is on finding small critters that are rarely encountered on coral reefs.

The survey should take no more than 5 minutes to complete. Participating in this survey is entirely voluntary and your identity cannot be connected in any way to your survey answers, and you can opt out at any time.

To access the survey please follow this link and you can email Maarten here.

Want to know more about ‪#‎MuckDiving‬? Here's a link to an article in X-Ray Magazine by Eric Hanauer.

The Underwater Marketing Company's 2014!

Sport Diver Magazine, Mark Evans, Apeks Aqua Lung, Shearwater Research, Suunto Dive Computers, TEKDiveUSA, Randy Thornton, Light Monkey, Tom Mount, Diving Awards, Rebreather Forum 3, RF3, Dr Richard D Vann, Dr Neal W Pollock, Dr Petar J Denoble, Girls on Gas, Rebreather divers, Inner Space, Divetech, Nancy Easterbrook, James Roberton, Poseidon Rebreathers, Steve Newman, Rosemary E Lunn, Roz Lunn, diving Cayman Islands, Scuba Radio, Greg Holt, XRay Mag, X-Ray Magazine, Anglesey ScubaFest, EUROTEK, advanced and technical diving conference, The ICC, Dive Rite, DEMA Show, The Underwater Marketing Company, New Product Showcase

2014 was a fantastic year for The Underwater Marketing Company. Rosemary E Lunn (Roz) regularly contributes to a number of diving publications, including Sport Diver Magazine and X-Ray Magazine. Getting your work printed is always special. But nothing is quite so thrilling as being featured on the front cover.

The first half of the year was taken up consulting on and establishing an inaugural technical diving event in North America; TEKDiveUSA. Roz and the Thorntons were supported and assisted by some amazing and talented Smurfs, and the international team of speakers, sponsors and exhibitors weren't bad either. A favourite memory was being grabbed by gleeful Tom Mount who was chuffed to receive the Lifetime Achievement Award.

From Miami Roz flew straight to Grand Cayman to work Divetech's Inner Space. If every dive centre was as well run as Nancy Easterbook's establishment, the diving industry would be in great shape. This week long event attracts rebreather divers from all over the world for a number of reasons, including the plethora of underwater attractions this tropical island offers. The highlight of Inner Space was being made an ambassador for Poseidon Rebreathers, a fun time machine with the ability to do some serious diving.

The summer saw the publication of the long awaited Rebreather Forum 3 Proceedings. (Click the link to get your free copy of this invaluable resource from this 2012 international safety symposium). Anyone involved with or diving rebreathers ought to read it.We attend a number of scuba shows and events throughout the World. In the USA Roz often bumps into Greg the Divemaster from Scuba Radio. This online radio show has been broadcast for 17 years. It is always good to be able to contribute to this programme.

In August, 200 divers descended on North Wales for The Anglesey ScubaFest. Diving, snorkelling, discover scuba, freediving clinics, kit try dives, bands, beach combing, beverages and bonne amid. £100 was raised for local charities and a good time was had by all.Time for another fab event. In September 500 divers, industry movers and shakers, explorers, experts and specialist exhibitors from all over the globe headed for the ICC in Birmingham. EUROTEK Advanced Diving Conference, the major European advanced and tech diving conference turned 4 this year! Our gorgeous gala awards dinner was even more glittering and we raised £4,000 for the Rubicon Foundation, thanks to the generosity of divers and sponsors alike.

It only seemed days later that it was DEMA Show in Las Vegas. Roz worked with Dive Rite on the launch of their new LX 20 Primary handheld torch. It was great to help produce a sexy display iin the New Products Showcase.So that is glimpse of some of the highlights of 2014 - a year of scuba event management, journalism and PR. Here is to a great 2015!

January 2014 Edition of X-Ray Magazine is out

XRay Magazine_scuba diving_Rosemary E Lunn_Roz Lunn_The Underwater Marketing Company_cave diving death_fluro diving_Doug Allan_Steve Lewis_Simon Pridmore_Poseidon SE7EN
The latest issue of X-Ray is out. Main highlights in this international diving magazine include;
  • Mouthwatering wreck diving; Norway's Frankenwald
  • Profile of BBC Wildlife Cinematographer Doug Allan
  • Fluorescent Night Diving
  • Steve Lewis Tech Talk feature on Exposure
  • Cuba's Gardens of the Queen
  • Indonesia's Bunaken
  • Solomon Islands' New Georgia
  • Simon Pridmore discusses Oxygen in Scuba Confidential

Plus news and discoveries, equipment and training news, books and media, underwater photo and video equipment, turtle news, shark tales, whale tales and much more...

Enjoy!
Download your free copy of X-Ray Magazine here (file format: pdf)

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