fairing for utility trailer
 

I'm seeking to reduce the aerodynamic drag of the trailer I use to haul windsurfing boards. When towing it using my Subaru wagon, my fuel economy drops from 30 to 25 mpg when driving at 65 mph. As part of an effort to upgrade the structure, I'd like to add a fairing to direct the flow of air above around the boards that are stacked on the trailer shown in photo.

One time I saw an advertisement of the trailer for towing motorcycles that had a front fairing like I would need, but I've not been able to locate it again. Can anyone point me to a source for an economical fairing. It need not be optimum as almost anything would be better than the sharp square corners on the present base.

First thought is wow, what a long tongue! The closer the trailer can be to the tow vehicle, the more the trailer can hide in the tow vehicle's draft. Beyond that, I'd consider building a hinged box around it all with radiused leading edges.

I've seen hinged box trailers for sale. A hinged box would be fine on highway, but sorry, it would be too much of a hazard where I go sailing. Side Wind gusts of 30+ mph that frequent Lake Isabella would likely topple such a top when open, and it needs to be open when at lake to access gear.