Sidemount- Principles For Success May 2026

If you clip a cylinder to your chest D-ring and bottom clip, but the tank's center of buoyancy is behind your center of gravity, you will roll onto your back (feet up, face to the sky). If it is too far forward, you will pitch head-down.

Success Principle: Trim is a property of the diver, not the tanks. Recreational backplate divers love their continuous webbing—one piece, no padding, minimalist. In sidemount, you cannot simply thread the same rigid straps sideways. The human torso is conical, and your shoulder blades move. A poorly fitted sidemount harness will rotate tanks into your armpits, pinch your neck, and cause lower back pain.

This article deconstructs the sidemount configuration into seven core principles. Whether you are rigging your first set of AL80s or trimming out steel LP85s for a 6-hour cave dive, these laws apply. The single biggest mistake new sidemount divers make is trying to solve buoyancy and trim problems with the tanks . They think, "If I move the tank up, I will sink my feet." Or, "If I slide it back, my chest will go down." Sidemount- Principles For Success

The first principle of sidemount success is that

Choose to succeed. Dive sidemount. About the Author: [Your Name] is a [Agency] Sidemount Instructor and technical diver with over [X] sidemount dives in caves, wrecks, and open water. This article is based on the curriculum of [Your Course Name]. If you clip a cylinder to your chest

Think of the "Ghost Diver"—your body, backplate (if any), wing, and exposure suit. When you remove the cylinders, you should be able to hover in horizontal trim, motionless, with your hands at your sides or crossed on your chest. You should require zero fin movement to maintain depth.

But here is the hard truth:

Why is this critical? Sidemount tanks are slung alongside your body. They are not structural elements of your trim. If you rely on tank position to fix a head-up or feet-down posture, you are building a house on a cracked foundation. As you breathe down the gas (changing tank buoyancy), or if you donate a tank to a buddy, your center of gravity will shift unpredictably. Strip your rig to the bare essentials (wing, harness, backplate). Perform a weight check. Adjust your ballast so you can hold a 10-foot stop with an empty wing. Only then should you clip on your sidemount cylinders.