How to Use Diver Propulsion Vehicles #scuba #scubadiving #freediving #ocean #underwater

August 12, 2022 - Comment

Diver propulsion vehicles (DPVs), or underwater scooters, expand your range dramatically without any additional physical exertion. DPVs first became popular with technical divers because they allowed deeper penetration into caves and shipwrecks. As battery technology and design advanced and costs declined, they became accessible to any diver. I teach DPV courses to local kids and



Diver propulsion vehicles (DPVs), or underwater scooters, expand your range dramatically without any additional physical exertion. DPVs first became popular with technical divers because they allowed deeper penetration into caves and shipwrecks. As battery technology and design advanced and costs declined, they became accessible to any diver.

I teach DPV courses to local kids and teens, and find the technology can be useful for many recreational and scientific purposes. My youngest DPV student, Santiago Ramirez, who is 13 years old, loves the feeling of jetting through the water. The underwater scooter also makes diving easier for his dad, who finds kicking challenging due to an ankle injury. A colleague straps his camera to his DPV

to survey fish aggregations. Google Street View, together with the XL Catlin Seaview Survey team, used DPVs and 360-degree cameras to map our world underwater. The applications are endless. Scooters can enhance your underwater experience in ways you never dreamed possible.

Underwater scooters fall into three main categories: manta boards, tow-behind, and diver-tug scooters. The manta board tows you behind a jet ski or boat. You hang on to the handles while being towed. You can angle the board down to submerge, or up to ascend. Tow-behind DPVs allow hands-free diving. You hold the scooter between your legs as you get propelled forward. The diver-tug type of DPV is the most common. Grasping one or two handles, the DPV pulls you through the water. Depending on the design and power, you wear a harness around your legs/torso to attach to the unit. It’s imperative you get the line that clips from the harness to the DPV sized correctly. Use a slipknot to help fine-tune adjustment in the water on your checkout dives. When positioned correctly, your arms will push slightly down on the device with limited effort, so your body and legs ride just above the prop wash. Clipping the DPV into your harness allows for the harness, rather than your arms, to pull the weight of your body and equipment forward. Turning your hand to the right or left allows you to steer. If the tow line is not correctly aligned, you will be incorrectly using the strength of your arms to tow your weight. You might not notice it right away, but fatigue can set in quickly.

Know Before You Ride

Operating DPVs requires acute situational awareness. In addition to running the vehicle, you need to control depth, buoyancy and navigation while monitoring air supply, dive conditions and your buddy’s whereabouts.

DPVs for snorkelers tend to be lighter units that are not pressure-tested to depth. DPVs used for diving are heavier out of the water because of the battery and the materials needed to compensate for increased pressure at depth. For safety reasons, DPVs need to be neutrally buoyant at depth. At times, you may need to strap the unit off to your BCD underwater. If it has any negative or positive buoyancy, it can potentially be dangerous. All DPVs should be attached with quick-release mechanisms that you practice disconnecting before your dive. If you dive in both salt and fresh water, you will need to adjust the buoyancy accordingly.

Start On The Surface

Before submerging on a dive, practice running the DPV on the surface. Know how to turn the unit on and off, and power up and down. You will want to know how to do an emergency stop if the unit gets stuck. You should be able to put your hand or an object, like a rock, into the propeller area to automatically stop the unit.

Before donning your scuba kit, practice using your DPV with just your snorkel gear. The first time you run a DPV, you will want to kick, but your fins do not help with propulsion, they aid your turns. This takes time to get used to. Arching your back, leaning your body to the right or left, and using your legs and fins like the rudder of a boat helps you turn with ease. You may want to experiment with different fins to see how they impact your turns and balance. Depending on dive conditions and depth, you will need either a light and compass around your wrist or attachments to mount them on your vehicle. Wrist computers are ideal when riding scooters so you can easily see your depth, time, no-decompression and ascent rates.

Avoid Hazards

Know how to avoid potential hazards. Kelp, eel grass, aquatic plants, soft corals and even fishing line can get caught in your propeller. If cruising over sand patches or silty environments, you can create a disorienting dust storm.

Discuss what to do if you become separated from your buddy before your dive. When cruising, it’s much easier to stay together with your buddy in a side-by-side position rather than having one person lead. Keep your head up and watch for jellies and siphonophores in the water. If you collide with these creatures, their tentacles can cause a nasty sting.
During the PADI DPV Underwater Scooter course, over two dives, a knowledgeable instructor helps you understand special considerations when operating an underwater scooter, including ascending, descending, reading local conditions, and proper maintenance.

Pro Tip

Create a checklist before diving with your DPV. Fully charge batteries and test the unit at the surface before descending to ensure it’s working properly. Be aware of your battery power throughout your dive. Make sure you always have an emergency action plan in case of failure or flooding.





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