This is the primary buoyancy element.
Made from XPS to ensure no water absorption. Skinned with a layer of PVC foam and as much FG/CF/Kevlar skin as the builder is prepared to carry. Designed as a sacrificial component to take and knocks and scrapes of normal operation ultimately with replacement in mind.
The front of the Underhull is shaped to correctly plane if the nose of the craft dips and contacts the water surface. Like the PMR1, these craft are very plough-in resistant.
I suspect that the planing shape will be improved over time. There hasn’t been much development on this aspect of small hovercraft design so it’s not well understood. I call the ridge on the centreline at the front the forefoot (a boat building term) although while it’s in the right spot, a forefoot is a component that connects the keel with the prow,.
