| Official Number: | ON 682 (RNLI) |
| Donor: | gifts from Mr. Stewart and his sister Mrs. W. Kendall |
| Station | New Brighton |
RNLB William and Kate Johnston (ON 682) is a lifeboat[1] that was stationed at New Brighton in the English county of Cheshire from the summer of 1923[2] until 1950. The lifeboat was designed as a prototype by James R. Barnett[3] who was a consulting naval architect to the Royal National Lifeboat Institution. She was the first Barnett-class lifeboat and at the time of her launch, she was the largest lifeboat in the world.[3]
Th motor lifeboat, designed by naval architect James R. Barnett, consulting naval architect to the Royal National Lifeboat Institution (RNLI), was a radical departure from their previous motor rescue boats, typically of around 45feet.[4] She was not self-righting as priority was given to an ability to reach port with a larger number of the rescued and to speed, even when awash.[3] [5] She was 60feet long with a beam of close to 15feet and a draught of 4inchesft6inchesin (ftin). The hull was constructed of timber and was divided into fifteen watertight compartments.[3] The lifeboat was also the first motor lifeboat to be built with flush decks, similar to earlier steam driven lifeboats. There was a semi-enclosed deck shelter which housed the on-deck helm position and which helped to keep the crew out of bad weather. Below deck there was also a cabin which could accommodate up to twenty four people; if necessary, the Barnett-class lifeboat was capable of carrying a total of 130 rescued people.[3]
The William and Kate Johnston was driven by twin propellers which were housed in tunnels and powered by two DE5-type six-cylinder submersible petrol engines of 80 horsepower, also designed by Barnett.[3] Each engine, with a separate fuel and cooling system, was housed in its own watertight chamber, and was capable of running even if the engine room became flooded and the engine was entirely submerged.[3] The engines' air intakes were set well above the waterline even when the boat was waterlogged. The Barnett-class could cruise at 9.5kn[3] and had an operating range of 300nmi.[3] The Barnett-class boats were also the first for the RNLI to rely solely on their engines for motive power, although they were equipped with a small staysail and trysail for stability purposes.