These plans are for an enclosed cab snow mobile.

This snow mobile folds apart for easy towing. When you get it to where you want it, put the ski back on and fire up the propeller. The motor used was a 65 hp engine from a Continental airplane. Attached to the prop, the boat pushes itself along on the skis.

From the plans:

"Four winters of hard use around International Falls, Minn., and also in neighboring Canada have proved the Merrymaker snowmobile to be a practical, rugged vehicle ideal for cold climates. The thrust of a propeller driven by a Continental aircraft engine drives the vehicle over snow and ice and, when it is necessary to transport the snowmobile over dry highways, it becomes a "self contained" trailer.

In about 15 minutes two men can remove the three runners, install two wheels and the unit hooks to a trailer hitch on a car for quick change of locations at highway speeds. The easy transition from snowmobile
to trailer was made possible on the original because it is built on a modified boat-trailer frame.

It is possible to build the snowmobile from the ground up by using the dimensions and drawings."