Visual Direction Indication for Ships

Extract

There is no doubt that everyone is agreed that a combination of visual and sound signals are a necessity, but, in view of the large disparity in the speeds of light and sound, the method of achieving this has not really been agreed upon, although a few countries supported the system of synchronizing the light and sound signals, thus bringing about the addition of Rule 28(c) to the Collision Regulations. I am, however, of the opinion that this synchronized system is not suitable, mainly because of the disparity between the relative speeds of light and sound. This could lead to confusion and misinterpretation by the receiving vessel; the degree of confusion depending on how far distant the receiving vessel is from the vessel giving the signals, when there is a sudden alteration of course immediately following the previous alteration.