Diesel locomotive set, and went into series production with other streamlined car sets in Germany starting in 1935. In the USA, diesel-electric propulsion was brought to high speed mainline passenger service in late 1934, largely through the research and development efforts of General Motors from 1930–34 and advances in lightweight carbody design by the Budd Company. The economic recovery from the Second World War saw the widespread adoption of diesel locomotives in many countries. They offered greater flexibility and performance than steam locomotives, as well as substantially lower operating and maintenance costs. Diesel–hydraulic transmissions were intrdouced in the 1950s, but from the
New Zealand DA class locomotive New Zealand DA class locomotive The New Zealand D class diesel-electric mainline locomotives operated on the New Zealand railway system between 1955 and 1989. With 146 locomotives, it was the most numerous class to ever operate in New Zealand, with five more than the A class steam locomotive. The class were A1A-A1A versions of the Electro-Motive Diesel G12 model, with the design altered slightly to run on New Zealand's rail system, and fit the small loading gauge. They were introduced between 1955 and 1967, and were the first class of diesel locomotives to seriously displace steam traction. Between 1978 and