They served as the observation cars on the famous Hiawatha trains from 1935 until 1948, when they were displaced by the new Skytop Lounge.

While retaining most aspects of the original design, Kuhler added ribbing along the sides and fins in the back.

[1]: 44–57, 259 The cars, like the rest of the Hiawatha equipment set, were painted in orange, maroon, and gray.

[2]: 23  The Milwaukee Road coined the name itself and used it in publicity beginning in February 1935, three months before the Hiawatha debuted.

[1]: 22 The first two Beaver Tail cars, the Nokomis and Wenonah, entered service on the original Hiawatha in 1935.