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.
I 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.
How 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.
The 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