By Brett Hemphill
Side mounting tanks were originally used as a secondary configuration for exploring underwater caves too small to be accessed by standard back-mounted cylinders. But in the past years, cave divers that had no interest in pushing through low, forbidding passage have found the use of side mount configurations convenient in standard cave exploration, open water wreck diving and solo diving.

Side mount systems offer increased easy of handling and mobility with dives that require transports in thick jungles, dry cave sections or any other location that requires divers, sherpas or pack mules to tote cylinders over long distances. Remote dive locations seldom have double cylinders available for technical diving, but often have a large supply of single cylinders that can be easily converted into side mount tanks.

Since the earliest side mount divers, such as Woody Jasper, Wes Skiles, and Lamar Hires, began this type of underwater exploration in the United States, many variations have been created and most ideas have been borrowed, tried and accepted or left behind. The first explorers to use sidemounted tanks were English sump cave divers. That phrase, sump cave, refers to a system where the passages are semi-dry or completely submerged under water. At this time, body harnesses used for repelling into or ascending out of the cave began serving a third purpose. By clipping cylinders to the waist or hip area of the harness, divers could traverse submerged sections of the cave without needing to haul extra scuba equipment throughout the dry tunnels. After traversing the sump into the dry chamber beyond, the side mount cylinders could be easily removed and transported to the next sump
.Training and gear configurations relative to cave diving have undergone many changes since their conception, and sidemounting is no different. The aspect that has undergone the most change, however, is the connection point of the cylinder. Configurations using large aluminum plates with fixed D-rings to moving hinges attached to waist and bottle, point of attachment seems to be reinvented most often. The most important thing a diver should take into consideration is how any given configuration will function in a worse case scenario.

Known as the Armadillo, this side mount rig allows two layers of two-inch webbing to form a firm and supportive point of connection. This enables the diver to easily remove tanks, in and out of the water. Underwater, the Armadillo pad keeps the tanks from shifting position even if the diver should completely invert. On rare occasions, side mount divers may have a need to back out of a small passage. In this situation, plates and other types of rigid metal connections have a tendency to pull up causing tanks to rise, possibly causing the plate to become wedged and thus making a bad situation worse. For this reason alone, the Armadillo was conceived. How it is attached to the diver and its shape makes backing out safer. The buoyancy control device (BCD-wings) are intentionally flipped over and the low-pressure inflator hose comes over or under the divers right shoulder. This helps to protect the connection point--where the low-pressure inflator enters the BCD--from impacting or rubbing along the cave surface in tight restrictions.
The simplicity of the shoulder harness, waist belt and crotch strap keep the system very clean and streamlined while eliminating needless straps, buckles and D-rings.Because the BCD-wings are sewn directly into the harness, the sidemount becomes extremely easy to transport and comfortable to wear prior, during and after the dive. The primary cave light canister can either be mounted on the diver's waist strap or butt mounted with quick release snaps. Snaps on the light enable it to be removed should it ever become stuck in a restriction.

Two methods of strapping the cylinder neck to the underside of the diver's arms have been tested. One incorporates a looped bungee that crosses the diver's middle back and can be slipped over the valves. The second is the use of attached D-Rings just below the diver's arms on the edge of the harness wings. A secured bungee on the cylinder neck is looped through the D-ring and stretched across the diver's chest to the opposite d-ring. This method also pulls the edge of the wings tight against a diver's sides.

The only downfall of the Armadillo harness is that they are all handmade and only available through Brett Hemphill or Advanced Diver Magazine. That is, of course, unless a diver owns his or her own industrial-size sewing machine. For more information see ADM's web site at

This article is a excerpt from ADM Issue 9, 2002