The "wind wagon,"The "wind wagon," a cross between a sailboat and a wagon, was proposed as a means to get gold-seekers to the west faster. On paper it worked: in practice, the prototype which was built sailed across the ground at an amazing 15 miles-per-hour. Then it crashed. The inventor was never able to produce a reliable version.
 

Another concept which was floated but never flew was an airline to California.
But in 1849 there were no planes, so the promoter proposed to fly prospectors
west on propellor-driven balloons which were powered by steam engines. 200
people signed up but the trip never happened.
 *- source PBS*