Am 19.03.2018 um 16:25 schrieb firstname.lastname@example.org [SwissRail]:
Actually, my information comes from editions of BBC and SLM magazinesIt's right that one unit was tested on the Rigi before being shipped to the USA. However, I can't see from which VRB unit they could be derived. My SLM book doesn't state anything like that but talks of innovations, later also used elsewhere.
VRB railcars 1-3 were built 1937 as SLM 3637-39, n° 4 was built after the same plans in 1953 as SLM 4088. Railcars 1-4 had two motors in one bogie and one bogie without motors, an arrangement that hasn't been applied later.
A new design came 1938 with the Rochers de Naye railcars. The motors were arranged longitudinal in the bogie. This arrangement was further developped and also applied to the railcars of GGB, WAB (with two longitudinal motors per bogie), ARB (also one longitudinal motor per bogie) and some others.
First M&PRR railcars:
14 SLM 4441 and BBC 1963
15 SLM 4442 and BBC 1963
each bogie has one longitudinal motor
VRB 5 was delivered in 1965, built by SIG, only the rack bogies came from SLM. They have two lateral motors per bogie.
(from SLM book 1871-1971)