Charles Evans Hughes, Eastern Air Transport v. South Carolina Tax Commission…
“ There is no substantial distinction between the sale of gasoline that is used in an airplane in interstate transportation and the sale of coal for the locomotives of an interstate carrier, or of the locomotives and cars themselves bought as equipment for interstate transportation. A nondiscriminatory tax upon local sales in such cases has never been regarded as imposing a direct burden upon interstate commerce and has no greater or different effect upon that commerce than a general property tax to which all those enjoying the protection of the state may be subjected. ”
