What is a Lifeboat?
A lifeboat is a boat which is used to run for life in case of an emergency situation on board ships (there can be lifeboats on beaches and offshore platforms as well but we will focus on lifeboats used on ships). As we know the ship itself is a big boat which has been designed keeping lots of complex mechanisms in place yet no ship is foolproof and could land into trouble some time or the other. The passengers or crew members on board at the time of distress require smaller boats to survive at sea till help arrives. Though this might seem a very scary thought to be floating on a small comfortless boat in the middle of the ocean filled with predators but this can turn into a reality and hence maritime regulations require the installation of one or the other lifeboat types on all ships, yatchs, research vessels and marine structures such as rigs and platforms.
Types of Lifeboats
There are various types of lifeboats in common use and the picture below shows the most elementary lifeboat which is nothing but a hand-propelled boat with oars and sometimes has a small outboard engine fitted. Of course there are some other accessories such as ration, water, medicines, EPIRB and so forth. Though this is a very good option in case of emergency, yet I would not feel very safe in this open sort of boat especially if the sea conditions are not calm. Even logically speaking how you would expect this tiny boat to protect you in case you ship capsized in a severe storm.
These types of boats are located at appropriate positions on board the ship and have a mechanism for lowering and raising of the boats during times of use. It is not only lowered during emergency but also during routine testing and safety drills involving life boats.
Another type of lifeboat is the totally enclosed lifeboat and as you must have imagined it is totally enclosed from all sides. You can see the picture of such a lifeboat and I am sure you will feel much safer in such a craft when in a distress situation than compared to the boat discussed earlier which I find more suitable for pleasure boating in a small amusement park lake. Another feature of this boat is that in case it gets capsized it can again return to its original position and though the passengers inside will get tossed around still they are afloat and safe.
A free fall lifeboat is a form of fully enclosed lifeboat which can be lowered quickly into water just by freefall under gravity once all passengers are seated inside and a quick release mechanism is activated. It is much more useful in a real panic situation where very few people might remember what all steps are required to be followed in the lifeboat launch process. The picture below shows such a lifeboat during actual release and dive action, and you can see that once the locking mechanism is released, the boat would simply dive towards water but the people need to be seated securely inside the boat to prevent injury.
The picture on the right below show another type of lowering mechanism which is used for non-fully-enclosed boats and even fully enclosed boats in some cases, and consists of lowering with the help of davit and winch arrangement. But for the rush in the emergency situation, this method seems much more civilized than being packed inside an enclosed boat and dumped into the ocean.
Freefall vs Normal Lowering
Lifeboats: Amberlay Marine, UK