One of the many joys of sailing is the opportunity to see things from an entirely different perspective than our landlocked friends and relations. And for me, never is the joy greater than when the sun dips below the horizon and the moon arises to illuminate a completely new journey over what was once the very familiar. Add to it some good music, food and friends and we can create a little of the ambiance that the great mariners of old may have enjoyed while crossing the seven seas.
Yet, the very fact that we may be on water that we think we know might foster a bit of apathy that could be dangerous when the sun is no longer over our shoulder. So the key to making an after dark sail safe and enjoyable is preparation while there is still light. What follows are the generalities in preparing for a lake sail after dark. A dark ocean presents even more considerations and difficulties and requires particular planning which I cannot cover in this short article.
Let's start with your boat. Are your position lights operating correctly and are the house batteries properly charged? Do you have a compass and a chart of the area in which you are sailing? What about some means of communication with the shore in case of emergency? These are some of the things that we seldom pay mind to in daylight on familiar water which become so important at night.
There are legal requirements for boat navigation/position lights at night depending on the length of boat. But beyond those requirements, you should always have a large powerful light to shine on the mainsail if another boat approaches.
One thing to consider is how your sailboat is perceived in the dark environment by other boats. Most power-boaters are not used to seeing and do not expect to see sailboats on the water after dark even though we have a perfect right to be there. Therefore, power-boaters have a tendency to dismiss lights that are not moving quickly enough in their minds and they can easily mistake our lights for shore lights. Add to this, the facts that the motor may not be the only thing aboard being "fueled" and after a tiring day on the water, the quickest way home is full speed ahead and you have a recipe for disaster. More than a few times, I have had powerboats run right up upon me going too fast only to bear away quickly when the mainsail became illuminated large and bright right in front of them.
The worst situation that I can think of sailing in the dark other than a collision would be for my crew or me (when single-handed) to become separated from the boat. During training, we all worked very hard at mastering our man overboard skills in the particular boat we were sailing during daylight. When is the last time that you actually had someone go overboard? You probably haven't. So when is the last time you even practiced this maneuver? Could you maneuver at night back to a small spot of light bouncing on the water where a friend of family member is waiting cold and scared? Do you have a way to get them safely back aboard? Remember Murphy's Law, if something can happen - it will and usually at the worst possible time.
If you have crew, one of the items you should brief is the location of the several flashlights or spotlights in good working order that you should have on board and to keep the light beam always on the victim in the water no matter what. Always keep the victim in sight was never truer than in this situation. It also goes without saying, but I will say it again that at night, we always wear our life vests even if we don't during the day; and I have gone to the additional trouble of attaching a plastic whistle to each vest so that someone in the water can sound an alert to help in their location in the dark.
You should also equip your boat with a safety drag line. The one I have is about 35 feet long and has floatation tied to one end. I deploy it at night and drag it behind the boat. The crew is briefed that if someone goes over the side, swim to the centerline of the boat and grab the line going by. In that way, we can hopefully stop and pull you to the boat without having to maneuver around in the dark. Don't forget to retrieve the drag line prior to starting the motor when it is time to dock.
My sailboat is a Rhodes 22, which has a fairly high freeboard. The best way and probably the only way back aboard is the stern swim ladder which is not easily operable in the raised position from the water. So either leaving it down or tying a line in a position to pull the ladder down where it is water accessible is very necessary for single-handing. Other equipment can be purchased for boats that don't have ladders to assist in re-boarding the boat; very important during the day-critical at night.
A compass helps you stay oriented and you should pay heed to compass headings where you sail during the day so that you can apply the information at night. I can assure you that even the most familiar body of water during the day will look quite strange the first time you see it on a moonless night. And so while this may add to the "adventure" aspect of a night sail, it will most certainly cause disorientation too. This is due to the fact that most all perspective between landmarks is lost because of no depth perception and you will find out that most all shore lights tend to look the same at a distance. So much so, that determining whether a light is 100 yards away or a mile is a challenge. And because two lights having the same relative intensity give us no clue as to their relative distances to each other, we have a very hard time distinguishing landmarks which are clearly obvious during the day. Getting experience sailing on clear nights when the moon is full in familiar waters before you venture out in complete darkness helps in understanding and adjusting to this phenomenon. In fact, I recommend your first night sail start in the daylight and then transition to darkness so that the changing visual cues can be better adapted to.
All sailors should be in the habit of checking the weather and winds forecast anytime they go out, doubly so at night. I recommend you reef your mainsail the first few times you go and choose a smaller jib whether you think it necessary or not. Being a little under-powered is much preferable to the alternative in a strange new environment. One advantage at night I have found is that the wind seems to be steadier in both direction and speed. This is probably due to no convective heating of the surrounding terrain by the sun. However, I have also noticed that any changes in direction and speed that do occur are liable to be quite pronounced, depending on what caused them. So if a front is approaching or storms are in the offing, I would steer clear and pick a different night. If Murphy's Law should overtake you, reef quickly and early or douse sails altogether and start the motor if available until the danger is passed. A freak thunderstorm usually passes pretty quickly and the wind should steady and moderate some after the initial passage of a front. It is best to avoid being there in the first place if at all possible until you gain more experience.
Finally, it is very important to let someone on shore know where we are going and when we plan to return. Advise someone of your "float" plan and stick to it as even most busy recreational lakes become quite devoid of other boats and any possible help they could provide us after dark. Also, most water capable law enforcement is only funded for daylight hours when the powerboats are present and are likely to be nowhere around. So we must have someone on shore to account for us, in case we don't return in a timely manner.
When sailing at night single-handed, I even call my wife with position reports and direction of sail periodically on my cell phone. The reason for this is that it will cut down considerably on the search area and bring help faster in case the worst happens. The same can be done with radio calls to marinas, etc. providing someone is available to take the call.
In sum, with good preparation and a good plan, sailing at night can be a new and very pleasurable adventure which once you do it; you will wonder why you never tried it before.