John Balmain Brooke was born in Auckland on 28 July 1907, the eldest of three children of Ernest Brooke, a commercial traveller, and Amy Isobel Balmain, a schoolteacher. He attended Belmont School and Auckland Grammar School before studying at Auckland University College and Canterbury College. Having gained a bachelor of engineering degree, Brooke returned to Auckland and joined the staff of Seddon Memorial Technical College, where he taught from 1930 to 1941. On 12 December 1936 he married Elsie Maud Hunt at the Holy Trinity Parish Church in Devonport; they were to have two sons and a daughter.
Jack, as he was known, was a renowned sailor and a founding member of the Wakatere Canoe Club (later the Wakatere Boating Club) at Narrow Neck, and used his engineering skills to become an innovative yacht designer. Brooke managed to produce inexpensive yet exciting designs that allowed young people to participate in yachting. Such craft included a sailing canoe, designed in 1926, and the 14-foot Wakatere class, designed in 1932. Because they were not adapted to the rough conditions of harbour sailing, the 14-foot snub-nosed craft were ultimately replaced by another Brooke design, the 11-foot 6-inch Frostbite sailing dinghy, designed in 1938. The Frostbite became the first of Brooke’s truly popular designs, gaining national competition status in 1946. The Wakatere Boating Club acknowledged his considerable influence by granting him life membership.
Prior to the Second World War, Brooke’s innovative designs featured prominently in other popular yachting classes, and by 1939 had claimed championship pennants in the 14-foot Y, 16-foot S and 18-foot V and M classes. Brooke’s contentious skimmer designs outperformed the traditional yachts in the popular 14-foot and 18-foot classes during the 1940s and won the national 14-foot championship at Rotorua several times in the early 1940s. In 1940 he gained prominence in keel yacht circles by designing Gleam , one of New Zealand’s first real light-displacement keel yachts. This successful C-class yacht, which quickly rose to the top ranks of its division, was later followed by other light-displacement designs such as Judith in 1950 and Whitewings in 1952. He was also responsible for a number of successful outboard-power boat designs.
During the Second World War Brooke was rejected for naval service on medical grounds. In 1941 he became chief engineer for the Physical Testing Laboratory (later the Dominion Physical Laboratory) in Wellington. His main task was to set up a sophisticated machine shop which provided tooling for the manufacture of munitions. Brooke determined that the high failure rate for bullets was caused by excessive tolerances during manufacturing. He and his team set about designing tools and gauges that produced finer tolerances, and developed manufacturing disciplines that ensured they were maintained. Such innovations greatly improved the success rate of munitions, and Brooke’s significant contribution to the war effort was acknowledged with his being made an OBE in 1948.
After the war Brooke was one of those instrumental in introducing scientific research into industry and manufacturing. Aided by his engineering background, he established what became the Auckland Industrial Development Division, a branch of the DSIR. With Brooke as its director from 1945 to 1970, the division worked closely with manufacturers and others to solve technical problems. Their range of work was enormous, from helping metal-casting foundries to assisting in the production of heart–lung machines for the medical profession. Brooke was renowned as a vocal fighter against industrialists who viewed scientific research as an unnecessary luxury, and against governments who expected his division to produce enough income to cover its costs. He also turned his attention to issues such as the pollution problems facing Auckland and the development of the Auckland Technical Institute.
Brooke maintained his passion for yachting. He had enjoyed crewing on Royal New Zealand Yacht Squadron yachts since 1925 and gained club membership in 1949. He later served on its general committee for 10 years, including two years as club commodore from 1969 to 1971, the club’s centenary year. In 1981, in recognition of his commitment to the club, he received life membership.
Brooke’s nation-wide success as a yacht designer was consolidated by the popular Sabot dinghy, designed in 1957, and the Sunburst training dinghy, designed in 1964. Destined to become national classes, these designs gained wide acceptance throughout New Zealand. Over 5,000 Sunbursts had been built by the late 1990s and the class is used for the inter-secondary schools’ yachting championship.
In addition to being a member of the Institution of Mechanical Engineers and of the Royal Institution of Naval Architects, Brooke was a director of Salthouse Brothers shipyard from 1971 to 1985. The highlight of his career in naval architecture came in 1971–72 with the design of Spirit of Adventure , a training ship for young people; he refused payment for this project. In 1979 he designed a similar ship, Ji Fung , for Outward Bound in Hong Kong. Brooke was a founding trustee and vice patron of the Spirit of Adventure Trust.
Jack Brooke designed over 250 yachts and built a great number himself. His overwhelming interest was in assisting youth involvement in yachting. In 1974, in recognition of his considerable contribution to New Zealand yachting, he was named the Bernard Fergusson yachtsman of the year. Brooke died on 6 August 1992, at the North Shore Hospital, survived by his wife and children. His son, Don, and grandchildren became prominent in competitive yachting events.