RV/MH Hall of Fame And Museum, Elkhart, Indiana

From the display:

The Spartan Aircraft Company, owned by oilman J. Paul Getty, built these homes in Tulsa, Oklahoma beginning after the end of WWII to utilize the surplus production capacity that had been built up to meet wartime airplane demands. They were recognized as the finest mobile homes available in the late 40s and early 50s. It features an all aluminum exterior assembled using aircraft technology, aluminum wall studs and roof rafters, and an all birch interior. The wrap around front window was a Spartan trademark.