Slower, higher risk, more complex
V-Lowers take time to set up properly. Always use a rescue vest so you can make a fast get-away. In heavy turbulent water, the rescuer may porpoise and get pulled under water periodically. The belayers and rescuer work as a single team, good communication via hand signals is vital. V-Lowers with a raft are usually a bit safer if set-up correctly. Overweight the downstream end of the raft so it doesn't take on water. A quick release knot is an important part of the set-up. As with most rescues, set appropriate downstream safety.
The main advantages of this technique is the ability to position a raft or person at the accident site with pinpoint accuracy. If lowering a raft into position, this typically provides a very stable rescue platform to work from. Some of the main drawbacks are it takes a fair amount of time to set-up and setup is often very complex. It is pretty easy to lower persons but very challenging to move back upstream. Use of a single wrap around a tree is often necessary as the forces are far higher than most people expect. Many fail to set a deep enough angle, a 45° angle or less is ideal - basically a very deep V.
V-lowers
Although V-Lowers have their use, they take a great deal of time to set-up and that needs to be factored into your decision. This technique requires a rescue vest, don't jury rig a quick release system. A major advantage with this technique is the ability to use pinpoint precision in placing a large platform like a raft at the accident scene in a reasonably safe manner. Many fire departments like this technique just for that reason.
The V-Lower is a technique for placing a rescuer or boat in a precise location in a rapid. They take a fair amount of time to set-up and are fairly complex. They are a poor choice for a heads down rescue but are an excellent choice where you have the time. Lowering an attached swimmer mandates the use of a rescue vest. The rescuer person in the water needs to clearly communicate their needs (like navigation) to the puppet handlers on shore. A quick release system is required even on a boat. Many Fire Departments use this technique as it provides a stable rescue platform and they don't get the chance to practice whitewater boating skills. Boaters on the other hand favor using a boat without rope attached since they have the necessary skills and it is much faster to set-up.
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