There are occasions when it may be appropriate to make a signal to attract the attention of another vessel. Obviously, as this rule states, any signal that is made should not be able to be mistaken for a recognised signal.

An example I came across recently, occurred during a nighttime entry to a small harbour. We were sailing towards the entrance, when the light of a north cardinal buoy appeared ahead of us, exactly where the main fairway should have been-and there should not have been a buoy! We continued cautiously, only to discover that the light was a quick flashing white strobe light, on a small angling vessel, at anchor-with no other lights, in the middle of the fairway!

This sort of incident can cause major confusion, if the weather conditions are difficult, they may cause a serious problem. We found that even in clear visibility it was very unsettling and caused us some delay.

On another occasion, we were entering Bradwell Creek, in the Thames Estuary at night. The channel is very shallow, and narrow and full of moored yachts, plus, a cross tide in some parts.

A difficult enough entrance as it is, but on this occasion a very bright light appeared just at the most difficult part, the light was shining straight on our vessel, and was so bright we could see nothing. The light appeared to be the working lights of a small fishing vessel, and it seemed to be on a mooring, so I thought that they were on deck dealing with their catch. Suddenly, I realised that in fact, the light was a search light mounted on a motor cruiser of about 40 feet, and it was motoring straight at us! Because the light was so bright we could not see any of the vessels moored around us, and were in great danger of hitting something. On top of that, when the motor vessel passed us, they had no other lights showing!

This is an example of what is meant by not embarrassing other vessels. It is very tempting to shine a light on another vessel, if you do, they can not see anything else and their night vision will be lost for at least ten minutes.

If you think that a vessel has not seen you, the best approach is to shine a light on your own vessel, this is particularly effective on the sails of a yacht. A torch should be kept to hand for this purpose.

Most small craft carry white hand held flares, that can be used to attract attention, in an emergency one of these is very effective. If you do use one, you will not be able to see much afterwards for a few minutes; it may help to keep one eye closed!

Go to test of Rule 36.

Go to rule 37.