The QE IV was custom designed and equipped for the rough 40-mile ferry route between St. Croix and St. Thomas in the U.S. Virgin Islands. The tandem-catamaran hull arrangement was conceived and tested by vessel owner Warren Mosler, to provide passengers the most comfortable ride possible while remaining affordable due to low fuel burn. To keep the fuel consumption and weight down, the entire vessel was constructed from carbon fiber. The novel design and material warranted extra scrutiny by Gold Coast Yachts and the USCG in order to be permitted to operate as a commercial ferry within the United States. The Gold Coast engineering team, along with subcontractors, conducted the most through engineering review the USCG has ever seen. That review included a complete Computational Fluid Dynamics study followed by a Finite Element Analysis for the entire vessel. A traditional first principles analysis was also conducted independently. All studies were then verified through Data Acquisition, which included measurements of strain and accelerations in various wave heights, heading, and loading conditions. With air-conditioning, comfortable ferry seats, and a smooth ride, passengers can enjoy a quiet crossing between the islands.