Knocker White is a Dutch-built tugboat, currently preserved as a museum ship at Trinity Buoy Wharf.
The Knocker White, originally the steam tug Cairnrock, was built in 1924 by T.Van Duijvendijk’s yard at Lekkerkek near Rotterdam, Netherlands for Harrisons (London) Lighterage Ltd. The steam engine by Crabtree & Co. and boiler by Blair & Co. Ltd were fitted at Fellow’s & Co. Ltd’s dry dock at Great Yarmouth. In the early years of the vessel’s history, the Cairnrock was used to tow Harrisons’ floating steam-powered coal elevator Wotan around the lower reaches of the Thames. The tug was designed for general towage work and had the standard facility of a drop-down funnel for up-river work that required passing under the bridges.
In 1960, the tug was acquired by Alfred White and then passed to W E White and Sons (Towage) Ltd in 1962. It was at this time that the tug’s name was changed and the original engine and boiler removed. Two Petters marine diesel engines were fitted with their associated fuel tanks. At this time alterations were made to the wheelhouse with an external forward companionway that provided separate access to the main cabin. The original funnel was replaced by another drop-down funnel made in around 1943 which was removed from the steam tug Pinklake.
The Knocker White continued to be used for general towage purposes by W E White and Sons from their base at Hope Wharf, Rotherhithe up until 1982 including work on the Thames and on the Solent. In November 1982, the tug was sold for scrap to Todd (Breakers) Ltd of Dartford, ending its 58 year working life. The Knocker White was not broken up immediately and was drawn to the attention of Museum of London staff in 1984 as a classic example of an early tall-funnelled Thames steam tug. It was acquired by the museum in March 1985.
In November 2016, Knocker White was acquired by Trinity Buoy Wharf to be repaired/restored and on public display, where it remains moored to this day.