Paul Spencer had a problem with words. Specifically, the word "human" in "human powered circumnavigation." Existing records permit athletes to fly across the world's oceans, stitching together the land legs with long-haul flights. For Spencer, a world record-seeking endurance cyclist, that arrangement left a basic question unanswered: if you skip the hard parts, in what sense was any of it human powered? His answer was to remove the option entirely, and to build the boat that would make that possible.
That boat is now in the water in New Zealand. Known as the Pedal Beast, it is a carbon fibre trimaran rebuilt around a continuous pedal propulsion system engineered for solo open ocean use. It does not accommodate flights. Every kilometre of ocean must be covered by sustained human effort, turning what might have been a philosophical objection to existing record rules into a genuine marine design challenge.
The vessel's origins predate Spencer's project by several years. Built between 2012 and 2015 as the Tasman Rower, the trimaran was designed by Craig Loomes of LOMOcean Marine specifically for Tasman Sea crossings. When the original rowing attempt was abandoned, the boat sat structurally complete but idle. For Spencer's purposes, it was exactly the right starting point.
Carbon fibre and foam construction had given the hull stiffness with low weight. The narrow form kept drag to a minimum. Trimaran geometry provided meaningful stability without the penalty of excessive wetted surface. The hull was fully enclosed from the outset, making it appropriate for offshore conditions without major structural changes. What needed replacing was the propulsion concept itself.
Rowing, as it turned out, was the problem. Ocean rowing wastes energy during the recovery phase, loses blade effectiveness in rough water, and produces an inherently uneven power output. Pedalling delivers continuous torque, suits longer durations physiologically, and manages fatigue more predictably over time. Both Spencer and Loomes reached the same conclusion: pedal propulsion was better matched to the demands of sustained human powered ocean travel.
The drivetrain became the defining feature of the conversion. A high inertia flywheel smooths the torque through each pedal cycle, eliminating the stop-start loading that undermines efficiency. Counter rotating propellers translate that smoothed output into near constant thrust. Hydrodynamic drag was removed wherever the design allowed. Propeller shafts and hubs sit above the waterline, eliminating the resistance that would come from fully immersed running gear. The propellers themselves, large diameter, low rpm, and high aspect ratio, were optimised by a specialist hydrodynamicist.
The low rpm propeller approach has a relevant precedent. Similar principles were applied to Turanor PlanetSolar, the first solar powered vessel to circumnavigate the globe, a project also designed by LOMOcean Marine and completed between 2010 and 2012. The focus in both cases is efficiency across extended duration rather than peak output at any given moment. Early sea trials on the Pedal Beast indicate speeds around four knots with a lower perceived effort than conventional ocean rowing boats.
The human body was the constraint around which every other system was engineered. A custom recumbent pedalling position reduces fatigue and improves power transfer, prioritising smooth mechanical motion over raw wattage. Walk boards, pulley covers, and considered service access improve both safety and the ability to maintain the boat underway. The enclosed cockpit is configured for long-term occupation, with adjustable windows managing airflow across headwind, tailwind, and crosswind conditions. Ventilation is treated as a designed system with real controls rather than a side effect of whatever gaps exist in the hull.
Autonomous operation over extended periods shaped the systems package. Solar panels support onboard electrical requirements. A watermaker provides self-sufficiency away from ports. Satellite navigation and communications are fully integrated. A dedicated lifeboat is carried, and the hull is self-righting in the event of inversion.
Practical risks encountered during planning were dealt with directly. Mid-ocean hull cleaning was identified early as a genuine operational necessity. Spencer incorporated shark deterrent systems from Sharkbanz into standard procedures, addressing the exposure that comes with working on the hull offshore. Risk reduction across the project runs through equipment choices, defined processes, and thorough planning.
The conversion work was carried out at Harkin Boat Works in Whitianga, with Loomes closely involved throughout. COVID-related delays pushed the schedule back but also created time for additional refinement of the design. The pedal drivetrain is now complete and the project has moved into final systems integration.
Sea trials are underway in New Zealand waters. A Tasman Sea crossing will function as the validation passage before the Pedal Beast is committed to global use. The full circumnavigation will combine ocean pedalling with overland cycling segments, with the boat transported between ports during the land legs.
