Abstract: A toroidal shaped or ring fuel tank located within the loft line of a blended wing body aircraft is disclosed. The ring tank may be used in an aircraft to store liquid hydrogen fuel with a reduced tank weight. The ring tank may be continuous with no tank end domes typically found on cylindrical pressure tanks, reducing tank weight for a given fuel volume. The ring tank configuration avoids increasing the aerodynamic shape of the aircraft and does not encroach on usable passenger or payload areas of the aircraft. In one example the ring tank may be configured in a nose down position such that the forward portion of the ring tank is outside the pressurized cabin area.

Abstract: A toroidal shaped or ring fuel tank located within the loft line of a blended wing body aircraft is disclosed. The ring tank may be used in an aircraft to store liquid hydrogen fuel with a reduced tank weight. The ring tank may be continuous with no tank end domes typically found on cylindrical pressure tanks, reducing tank weight for a given fuel volume. The ring tank configuration avoids increasing the aerodynamic shape of the aircraft and does not encroach on usable passenger or payload areas of the aircraft. In one example the ring tank may be configured in a nose down position such that the forward portion of the ring tank is outside the pressurized cabin area.

Abstract: An expansion joint is provided for joining adjacent sections of a structure. The expansion joint includes a first generally planar member that is configured to allow sliding of a first portion of at least one section of a structure thereon. Second and third generally planar members are configured to allow sliding of a second portion of at least one section of the structure thereon. The second and third members are substantially co-planar with each other and are substantially parallel to the first member. The second and third members are vertically spaced-apart from the first member. An expansion device is interposed between the second and third members. The expansion device accommodates expansion and contraction due to thermal effects of the second and third members and maintains horizontal alignment. Each surface panel may be removed independently for replacement or repair.