Abstract: Hydrofoil apparatus comprising a first hydrofoil member (1) having chord and span dimensions and positive hydrodynamic pitching moments, a second hydrofoil member (2) having chord and span dimensions and positive hydrodynamic pitching moments, connection means (3) for connecting the first and second hydrofoil members (1, 2) together such that they are able to articulate about the connection means (3), at least first and second bridle members (4, 6) which are for enabling the hydrofoil apparatus to be towed and are such that the first bridle member (4) is articulately attached at one end (5) to an outer end portion of the first hydrofoil member (1) thereby forming a first pitching axis (BC), the second bridle member (6) is articulately attached at one end (7) to an outer end portion of the second hydrofoil member (2) thereby forming a second pitching axis (DE), the first and second pitching axes (BC, DE) forming an angle such that a component of hydrodynamic lift generated by the first hydrofoil member (1) and