Life Rafts: Part 1

After 76 days adrift in his life raft, Steven Callahan was rescued and a legend was born. He is just one of the many lives that have been saved by the development and proliferation of inflatable life rafts. Today we will examine the two types of life rafts, and the functions they share as well as how they differ. The valise or soft shell life raft that's designed to be stowed in the lazarette or down below, and the canister life raft. For all commercial vessels, and the majority of serious cruisers, canister rafts are the way to go. There are several reasons for this, several big ones being the valise are not as suitable for automatic deployment as there is no real way to mount them properly so that they will do their thing by themselves without risking chafing through the soft cover. So your only option is to manually take them out of lazarette, secure the painter, and toss it overboard. Storage is often an issue with people stowing them in a back storage locker or way forward in the v-berth which makes for very poor access in the event you need to deploy it quickly. Plus you have to imagine that you're in big seas and now you have to drag a 40 - 80lbs life raft out of its storage location, possibly up the stairs through the companionway into the cockpit, then secure the painter and then toss it over. That could easily be more time than you have. So in terms of safety and ease of use, canister life rafts are vastly superior. That being said, if you have a choice between no raft and a valise, take the raft.

Regardless what type of raft it is, most share similar operating principles. Once in the water - whether manually released or automatically (we’ll discuss this more shortly) you will pull on the painter (the only line coming out of the raft) until you pull all 10-30m of line out and then give it a nice hard yank to activate the inflation mechanism. It is extremely important to ensure that the end of the painter is secured to a appropriate point on the vessel. With a canister raft, this will be pre-rigged, normally to the breakable link on the hydrostatic release secured to the cradle. A hydrostatic release is triggered (as the name suggests) by hydrostatic pressure - usually 1.5m - 4m. At that depth, the pressure sensor will trigger a razor blade which will cut the line that's holding the raft in place allowing it to float up to the surface. If left unattended, it will keep bobbing at the surface as the painter line feeds out from inside of the raft. Once fully extended, the tension on the painter will activate the inflation mechanism. With a valise as mentioned above, this must be done prior to throwing the raft overboard. Besides the additional time needed to do this, one other issue with this type of raft is that if the vessel sinks after the raft has been deployed, the painter can very well pull the raft apart as it is pulled down by the sinking vessel and must be manually cut to avoid destroying the raft. This is just one more single point of failure. For canister rafts with the painter secured as above, the breakable link prevents this occuring. The breakable link is a red plastic component in the hydrostatic release assembly that is designed to break at a certain amount of force, less than what would damage the raft. So as the vessel sinks, if the line is not manually cut, the link will break and release the raft. An excellent illustration of this function is seen in this video where the 40m M/Y Saga sinks of the Italian coast in August of 2022. At timestamp 0:24 as she sinks by the stern, you can see the first raft pop to the surface, after being freed by the hydrostatic release. Then at 0:35, you can see the rafts begin to get pulled under as the vessel continues to sink, but settle back on the surface as the breakable links do their jobs.

Now, not all canister rafts are mounted with hydrostatic releases as it is an additional expense to owners, but is definitely the preferred method and is well worth the money. The reason for this is that if you have a manual release, it is exactly that it's manual. It requires a person to come up and pull the release. If for some reasons no-one was able to do this, the raft is going straight to the bottom with the boat.

And while the hydrostatic release is a great system, it is important to note that it is a last resort backup, and that the preferred method for deploying a raft is manually. You don't want to be sitting in the water for however long it takes for your boat to sink and your raft to deploy before getting in. Ideally you want to get the raft deployed, get all of your provisions in, get everything you might need together, get everybody accounted for and mustered on deck, and get everybody into the raft in a safe and timely manner. If you accomplish this, it is very very important (I cannot stress this enough) DO NOT CUT THE PAINTER LINE UNTILL THE RAFT IS ABOUT TO GET PULLED UNDER. There is a saying that you “never step down into a raft.” And while it does make sense literally, what it really means is you need to stay with the boat until you are 110% sure it is going to the bottom of the ocean. The reason for this is: there have dozens if not hundreds of accounts of boats that have been found partially sunk, upside down, or in pieces days weeks later by search and rescue, but they never find the people who abandoned ship into the life raft. So you want to keep yourself with your boat (or pieces of it) as long as possible, until it threatens to pulling you down (or catch you on fire). That’s not to say you shouldn’t deploy your raft if you've determined that the boat is going to sink. By all means do as much as you can to prepare in advance. Just don’t disconnect your painter until you absolutely have to. Use that time to collect any useful items or even just flotsam floating around and tie it off to the raft. The bigger the target you are for search and rescue to find the better off you’ll be.