Mace-Trefethen SeamasterThe Mace-Trefethen Seamaster is an American single seat seaplane racer.Design and developmentThe Seamaster was built by Alfred and Thomas Trefethen and Harvey Mace, using components from the PAR Special pusher monoplane. It is a single place, mid-wing seaplane with a Y tail layout and a single fuselage-mounted float. The pusher propeller configuration of the PAR Special was modified to that of a conventional tractor layout.