[1] In the early 20th century, NZR sought a means of providing economic services on lines with low traffic, including some suburban routes and to provide a faster alternative to mixed trains on rural lines.
It aimed to develop a light self-powered vehicle that could operate economically even with low passenger levels.
[2] The MacEwan Pratt petrol railcar of 1912 did not pass its tests and never entered revenue service.
The traction equipment, underframe, and bogies were provided by British Westinghouse and were fitted to a wooden body that had been built by NZR at the Petone Workshops.
[1] The wooden body largely resembled a railway passenger carriage, though the driving compartments fitted at each end had an appearance similar to contemporary trams.