A. L. Beattie

Beattie was almost instantly faced with a problem upon appointment as Chief Mechanical Engineer: New Zealand's railway network was expanding, traffic volumes were growing, faster speeds were required, and accordingly, a more powerful type of locomotive was required.[8] Furthermore, although this new class was to haul the heaviest and fastest expresses, it was to burn low grade lignite coal from Canterbury and Otago. Baldwin Locomotive Works recommended a camelback design to solve the problem, but Beattie conceived the idea of an enhanced 4-6-0 U^B class locomotive with a two-wheel trailing truck to support a wide Wootten firebox.[9] This created a 4-6-2 wheel arrangement under Whyte notation, and an order was placed with Baldwin for thirteen locomotives to Beattie's specifications in 1901. These locomotives became the Q class, and the first entered service on 24 December 1901[10] after being shipped across the Pacific Ocean. This voyage led to the 4-6-2 arrangement being nicknamed the Pacific type, and it became a popular arrangement worldwide.[8]

Described as the "triumph of Beattie's term in office", the A class was designed in 1905 for service on the Main South Line and the nearly-complete North Island Main Trunk Railway.[11] It was a further development of the Q class and earlier 4-6-0 designs such as the U class, seeking to rectify faults with those designs and improve efficiency and hauling power. Beattie created the initial design before passing it on to Chief Draughtsman G. A. Pearson to complete,[12] and when the first members of the A class entered service in 1906, they were considered to be the country's most handsome locomotives.[13]

After pioneering the Pacific wheel arrangement, Beattie went on to pioneer the 4-8-2 Mountain type. The A class locomotives were not sufficiently powerful to tackle the steep grades on the North Island Main Trunk, and Beattie's solution was the 4-8-2 X class.[14] Designed in 1908 for the opening of the Trunk, the first of eighteen Xs entered service on 9 January 1909,[15] and they were some of the largest and most powerful locomotives in New Zealand.[16]

Beattie introduced a number of other classes during his term, though none so notable as the A, Q and X classes. These included tank locomotives such as 1903's W^F class, 1910's W^G class, and 1913's W^W class.[17] Beattie was also one of, if not the, first to employ the 4-6-4T arrangement – the 1902 conversions of three B class locomotives into the W^E class and the W^G and W^W are some of the earliest examples in the world of the 4-6-4T arrangement.