A boat may sink for several reasons. If there are missing drain plugs, or if a Captain neglects to replace removed drain plugs, a boat would take on water while it is not moving. Or, if a hose in the engine bursts or isn’t tight enough, you may find your boat taking on too much water (the best way to avoid this is to check for corrosion or breaks in the hoses and fittings of the cooling system before taking your boat out). If the transom lies below the water line, the boat could allow water onto the deck and eventually sink. This catastrophe can be averted by being sure not to store any heavy equipment or items in the stern of the boat, rather distribute their weight evenly along the ship. Sometimes, it is just a navigational error, and you strike an object with your boat.
If you have struck something, and there is a hole in the boat, try to plug it up with cushions, doors, etc. and remove more water than is coming in. If your boat is definitely going under, assign tasks and try to stay calm. One person should be gathering all flotation devices (PFDs and life rafts) that are available, another should be radioing for help, and another should be collecting emergency items, such as flashlights, flares, fresh water, food, mirrors, sunscreen, batteries, radio, matches and a first aid kit. But above all, try to stay calm.
So your boat may be going down, but at least you have one life jacket per person on board…right? The law requires that each boat provide one PFD on board for each person you are carrying. Maybe you have a raft instead. These are extremely helpful, if you can afford them (at around $4,000). Rafts do have their flaws though, so be prepared and make sure you have PFDs as back-up precaution, just in case your pre-packaged inflatable is damaged.
While waiting for rescue, please take note that being adrift at sea causes various psychological problems and distressful conditions, where all you see for a prolonged period of time is open water. Keep your brain in a healthy state by playing word games and discussing future plans. This is imperative for your state of mind and is also a motivational tactic for your peers. Remember that drifting is a good thing; the further you drift, the more likely you are to reach land. Be cautious when you are in the heat for a long period of time. Even if your raft has a cover, you are still prone to dehydration. Ration your fresh water and under no circumstance should you ever drink sea water, which will increase the rate of dehydration.