When North American railroads started caring a bit less about luxury and speed and were more focused on costs and efficiency, the BUDD company turned it's efforts away from making lightweight, speedy streamlined passenger coaches to a form of rail diesel car, or RDC. Railroads in the US were required to maintain passenger service even on unprofitable lines. The RDC was the perfect solution, and they were well received by both passengers and railway managers. Many exist on preservation lines hauling tourists, but several still see revenue service. I believe VIA still operate around 8 of them on smaller branch lines in Canada. TriMet in Portland bought a few from Alaska after the original DMU supplier for their WES line went bankrupt in the middle of filling the order. They featured cabs at both ends, some were powered trailers without cabs to be sandwiched between two standard RDC units, they came as coach units, baggage/combine, baggage/RPO and so forth. Most were 85 feet long, while the baggage/RPO cars were 71 feet long to compensate for the extra weight when loaded. Here we see ex-Alaska RR 702 and 711 departing Beaverton, OR 702 in Anchorage, 1997 B&O (ex-Santa Fe) RDC-1 #1913 in Baltimore, 1970 Canadian National RDC-3 #6350 at Niagara Falls on track 2, 1970. That's Flying Scotsman on Track 1.