Based on the
success of the 52-ton MIDFOIL, Navatek received
funding from the Office of Naval Research to convert an existing
Navy Surface Effect Ship (SES) to a lifting body ship. Work on this project began in 2000 and resulted in the U.S. Navy
large-scale technology demonstrator craft "Sea Flyer." Using a surplus Navy SES-200 significantly reduced project costs. During the
two-year project, Navatek removed the existing SES air lift system
and all related components, and installed a 160-ton Navatek underwater
lifting body incorporating a new propulsion drivetrain (engines,
gearboxes, shafts and propellers) within the lifting body. This
allows the craft to be operated with variable immersion as speed
increases, with the parent hull fully out of the
water at maximum speed.
An aft crossfoil was included for pitch
and roll control, along with Navatek's proprietary, adaptive ride enhancement system (ARES).
Launched in
June 2003 by Navatek sister company Pacific Shipyards International, the 165-foot, 30-knot "Sea Flyer" (originally named "HYSWAC") has a full-load displacement
of 320 LT. It demonstrated significant payload-carrying capacity with no degradation in top speed, During successful sea trials in summer 2004, Sea
Flyer confirmed on a large scale the major benefits of
underwater lifting bodies verified through CFD
studies and on the earlier, small-scale, 52-ton MIDFOIL.
