Billy Twofeathers' locomotive is named the Rainbow Sun and is one of several that run on the Indian Valley Railroad. In the opening sequence for Shining Time Station, it was portrayed by the Union Pacific #844, a 4-8-4 locomotive built in 1944 which was the only steam locomotive in the US to operate continuously since entering service, having never been retired. The 844 is still active today as part of UPs steam program. In Thomas and the Magic Railroad, it was portrayed by the Strasburg Rail Road's #475, a 4-8-0 locomotive built in 1906 and formerly on the roster of the Norfolk and Western Railroad. It is one of only few N&W 4-8-0 Mastodon locomotives preserved, and the only one of its class operating. #475 is still operating today as one of Strasburg's main locomotives. This engine was also featured in A Wonderful American Journey with Thomas and Connie, though not as the Rainbow Sun.
- The whistle sound used for the Rainbow Sun is later used for Rocky in Edward Strikes Out, Victor on the Guess Who? Puzzles, Timothy on the official website, and Carlos in The Great Race. This sound is often used in TV and film, originating from the sound effects company Sound Ideas.
- The Rainbow Sun was seen in the Thomas and the Magic Railroad (activity book) but it was illustrated as an E2 class tank engine like Thomas.
Please visit the Shining Time Station wiki, based on the spin-off series of Thomas and Friends.