Commonwealth Lightships, Australia

Commonwealth Light Ship (CLS) No. 4 was one of four unmanned rivetted steel lightships built at Cockatoo Island Dockyard, Sydney, Australia in 1916-17. The 21.94 metre long vessel was originally equipped with an acetylene light, activated by a sunlight-operated valve, and fed by a six-month supply of acetylene gas in onboard tanks. An automatic mechanism controlled the flow of gas to produce a code of light flashes, while a bell tolled with the rolling of the ship. The bright red colour scheme was also easily recognised by sailors during the day. CLS 4 spent much of its life in the Gulf of Carpentaria, but spent the last years of its life in the Bass Strait oilfields as a traffic separator. It was retired in 1985 and replaced by a modern lightship.

Photo taken 27 October 2014, Australian National Maritime Museum, Sydney

Commonwealth Light Ship (CLS) No. 2, an unmanned navigational aid that was moored on the Carpentaria Shoal in the northern Gulf of Carpentaria, 50 miles west of the Torres Strait, between 1926 and 1983. One of four such vessels built at Cockatoo Island Dockyard in Sydney, Australia in 1916-17, the light ship measures 23 metres long and 8 metres wide. Each lightship would spend two years on station whilst a second vessel was in port being refurbished and refitted with 80 new acetylene tanks to power the navigation light; tugs would then tow the refuelled light ship to its station and return with the other light ship for its own refurbishment and refuelling. Each light ship was secured to the seafloor by 180 metres of anchor chain, and after two years on station the decks of the light ship could be covered in up to 100mm of slippery bird droppings.

Photo taken 26 November 2016, Queensland Maritime Museum, Brisbane

Photo taken 26 November 2016, Queensland Maritime Museum, Brisbane