Sound signals on the tidal Thames

Boating on the tidal Thames Teddington to kew Kew to Wandsworth Wandsworth to London Bridge Moorings Passenger boats Bookshop Bits & pieces Links	Boating on the tidal Thames : Sound signals These signals should be made by all power driven vessels to indicate their intended actions to other vessels. According to the PLA, small craft are strongly urged to use sound signals. In practice though, they tend to be used mainly by commercial vessels. Whether you use them or not, it is as well to remember what they mean. One short blast I am altering my course to starboard Two short blasts I am altering my course to port Three short blasts My engines are going astern Five or more short and rapid blasts I do not consider you are taking sufficient action to keep clear of me Four short blasts followed by one short blast I am turning around to starboard Four short blasts followed by two short blasts I am turning around to port One prolonged blast I am about to get underway, ie depart from moorings, jetty or dock entrance Two long blasts followed by one short blast I am about to overtake you on your starboard (right) side Two long blasts followed by two short blasts I am about to overtake you on your port (left) side One long, one short, one long, one short - the reply by the vessel being overtaken A "short blast" means a blast of about 1 second duration, a "long blast" is 4-6 seconds duration (although you may find in practice that the durations tend to be rather shorter than this) Source: The PLA booklet The Tidal Thames - a pleasure users guide
	The Tideway pages are maintained by John Kennett Comments, corrections and additions are always welcome