In one embodiment there is provided a flying toy that can be manually pumped with air. The pressurized air is kept in a canister and use to drive a propeller to propeller the toy for flight.

A fuel tank is disclosed including a lower cover and an upper cover. The lower cover or the upper cover includes a panel assembly. The panel assembly includes a panel and a stringer attached to the panel. The stringer includes a pair of portions which are spaced apart in a lengthwise direction of the stringer and connected to each other by a bridge. Each portion is connected to a respective end of the bridge, and each end of the bridge deviates away from the panel. The stringer includes reinforcement fibres which extend between the portions via the bridge. Each reinforcement fibre deviates away from the panel at each end of the bridge. The stringer includes a stringer recess between the bridge and the panel, and a flow passage in the stringer recess through which fluid can flow across the stringer.

Aspects relate to blended wing body tankers and methods of use. An exemplary blended wing body tanker includes a blended wing body, a first fuel store located within the blended wing body and configured to store a first fuel, a fuel offloading system operatively connected to the first fuel store and configured to offload the first fuel to another aircraft in flight, a second fuel store located within the blended wing body and configured to store a second fuel different from the first fuel, and a propulsion system powered by the second fuel and configured to propel the blended wing body.

Aspects relate to blended wing body tankers and methods of use. An exemplary blended wing body tanker includes a blended wing body, a first fuel store located within the blended wing body and configured to store a first fuel, a fuel offloading system operatively connected to the first fuel store and configured to offload the first fuel to another aircraft in flight, a second fuel store located within the blended wing body and configured to store a second fuel different from the first fuel, and a propulsion system powered by the second fuel and configured to propel the blended wing body.

An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2≤R≤25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2≤R≤25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

A blind fastener is disclosed having a head, a shaft with a tail, a tail of the blind fastener including the tail of the shaft and a sleeve surrounding the tail of the shaft, and a barrier secured to the tail of the blind fastener. The sleeve is configured to expand away from the tail of the shaft to form an expanded sleeve which is forced against a face of a workpiece to clamp the workpiece between the head and the expanded sleeve. The barrier is configured to be forced against the face of the workpiece to form a sealed cover around the tail of the blind fastener.

A blind fastener is disclosed having a head, a shaft with a tail, a tail of the blind fastener including the tail of the shaft and a sleeve surrounding the tail of the shaft, and a barrier secured to the tail of the blind fastener. The sleeve is configured to expand away from the tail of the shaft to form an expanded sleeve which is forced against a face of a workpiece to clamp the workpiece between the head and the expanded sleeve. The barrier is configured to be forced against the face of the workpiece to form a sealed cover around the tail of the blind fastener.

A blind fastener configured to be installed in a bore of a given length is disclosed and having a sleeve member configured to deform during installation of the blind fastener; a bolt member at least partially received within the sleeve member; and an insulating member fixedly disposed on the sleeve member. The sleeve member has a predefined outer surface region that is arranged to be disposed within the bore after installation of the blind fastener. The insulating member and the sleeve member are mutually configured such that the insulating member is present on a first sub-region of the predefined outer surface region and is not present on a second sub-region of the predefined outer surface region. Each of the first and second sub-regions comprises a complete circumference of the sleeve member.

A blind fastener is disclosed having a bolt part, a sleeve part, and a tubular insulating sheath. The bolt part is at least partially received within the sleeve part. A first end of the sheath is retained on the bolt part such that relative axial movement between the first end of the sheath and the bolt part is substantially prevented. The blind fastener is movable between: a pre-installation configuration in which the sleeve part has a first axial position relative to the bolt part and a predetermined section of the sheath is adjacent an outer surface of the sleeve part; and a post-installation configuration in which the sleeve part has a second, different axial position relative to the bolt part and the predetermined section of the sheath is adjacent an inner surface of the sleeve part.