This is 'Within', a human powered prototype boat designed for a human powered trans Atlantic record attempt.
It is based on a Nimbus Hyak tandem kayak which is 19 feet long by 28" wide. The kayak deck has been removed and the custom full deck that you see in the photo has been fabricated which will be permanently bonded to the kayak hull. The aerodynamic deck will feature a wrap around window and a round hatch on the side at about water level for entry/exit. The boat is propelled by pedals that turn a chain that runs down to a right angle gear box which spins a 2 blade propeller
Stability will be accomplished by a weighted keel suspended below the boat, or ballast in the hull, or a combination of both.
There are three water tight compartments: the cockpit where Greg will sit and pedal, the rear cabin where Greg will sleep, and the front supplies storage cabin. Solid buoyancy compartments in the bow and stern will ensure that Within cannot sink. Air trapped in one or more of these three compartments, along with the ballast will ensure that Within flips upright if capsized.
At 150 watts of input power, 80 rpm, our predicted speed will be about 9 kph. The boat speed calculator excel file is here: Boat Speed Calculator. note that the default weight does not include the full deck.