Abstract: A joining structure adapted to join adjacent tube structures together while providing high strength with low weight. The joining structure may be of composite materials, and may include warp tows in the longitudinal direction of the tubes and have weft tows cross-woven into a fabric, which may be a carbon fiber. The joining structure may be Y-shaped and adapted to join three composite sheets together. The weft tows may also be wound around a central cluster of tows, or tows, which may provide extra strength. The tubes may be pressurized in use, such as in an aircraft fuselage.

Abstract: A propeller blade pitch control mechanism configured to adjust and control the blade pitch of the blades of a multi-blade propeller simultaneously. The pitch control mechanism may have a pitch plate which is raised or lowered along a liner path along an axial direction using a linear drive, which may be a power screw. The pitch plate is coupled to the blade roots with kinematic links which transfer the linear axial motion of the pitch plate along the propeller spin axis into rotary motion of the propeller blade roots, thereby controlling the pitch of the propeller blades. The propeller pitch control mechanism may include springs or gas springs adapted to place the propeller blades in a low drag position in the event of failure of the blade pitch control mechanism.

Abstract: A joining structure adapted to join adjacent tube structures together while providing high strength with low weight. The joining structure may be of composite materials, and may include warp tows in the longitudinal direction of the tubes and have weft tows cross-woven into a fabric, which may be a carbon fiber. The joining structure may be Y-shaped and adapted to join three composite sheets together. The weft tows may also be wound around a central cluster of tows, or tows, which may provide extra strength. The tubes may be pressurized in use, such as in an aircraft fuselage.

Abstract: Boats and suspensions are provided, wherein the boat includes at least one hull, and at least one sponson, the at least one hull and at least one sponson connected by a shock-absorbing suspension member. The suspension greatly reduces the accelerations of the main hull, such that the hull accelerations are generally substantially less than the accelerations of the sponsons at selected speeds.

Abstract: Boats and suspensions are provided, wherein the boat includes at least one hull, and at least one sponson, the at least one hull and at least one sponson connected by a shock-absorbing suspension member. The suspension greatly reduces the accelerations of the main hull, such that the hull accelerations are generally substantially less than the accelerations of the sponsons at selected speeds.