Amtrak's “Rainbow Era” Like its locomotives, all of Amtrak's rolling stock was inherited from predecessor railroads such as Penn Central. Since there wasn't time enough to implement uniform branding on Amtrak's fleet come May 1st, 1971, most trains were comprised of varied rolling stock from multiple railroads resulting in a colorful, or rainbow-like appearance. By 1972, Amtrak developed its Phase I livery and began repainting its fleet of heritage coaches, however due to the size and service demand of the fleet, this process took several years causing the “rainbow era” to last well into the decade.