The "dillon mini tunnel" gt pro racing tunnelboat. redesigned for 2014 see the new plans. also available: cockpit plans can be adapted to the mini tunnel. The tunnel hull is a strange ‘bird’. while the tunnel derives much of its high performance from air lift, it depends at the same time on its planing interaction with. Click on buttons above for online study plans: welcome to our site there are buttons above that link to study plans below is a knowledge base of frequently.