I have built a version of the airhead. Works well now that I have the ergonomics and bugs worked out. The vent pipe should be higher than your
head so the wrong wind won't blow the smell your way. Extensions can be used in port. With a
weather cocking vent cap ,I haven't used the fan except when dumping. A turbine would work well. Painting the vent pipe black may create a thermnal draft in the sun as it heats up.
The peat moss under moss covered logs works well for composter. Its far simpler and ligher than a regular head.
They are overpriced for molded plastic but easy to build. It is labour intensive to build a one off. If you have time and little
money, building on eis simpler. If you have
money an dlittle time , buy one,altho I have heard they are back logged 8 months on orders.
They will become extremly common. They sure beat hell out of holding tanks. They even leave you something to mail to the politiocoes .
Brent