The Ocean Crossing Kayak is the first stage in an experimental project - some ocean going kayaks are quite large with volume to carry extensive stores and are made from exotic materials to keep weight down - some have 'castles' at bow and stern so that they are self-righting. With this design I have kept weight and size down to make it a more viable build for the backyard un-sponsored long distance kayaker - a first step into this type of canoeing which would help you to answer questions on how/where you would sleep, what stores to take etc - so she is a test bed to help prepare for long distances.
Construction is simple and lightweight stitch and tape plywood, she has storage areas fore and aft with built-in floatation at the ends and each side of the cockpit. She has a 'castle' behind the paddler which is accessed through a water-tight hatch - this along with optional floatation tubes above the paddler offer self-righting capabilities but ultimately how big the tubes need to be will come down to experimentation with how much in the way of gear and stores is carried. She can be built as a large kayak for long distance cruising without these flotation areas. Ballast can be carried if required.
The drawings give details for the batwing rig, offset pivoting board and rudder but again these are optional.