Abstract: Embodiments disclosed herein include fastener assemblies. In an embodiment, a fastener assembly comprises a sleeve with a hole, an inner surface, and top and bottom ends. The top end has a planar surface, and the inner surface has a cylindrical surface. The fastener assembly includes a fastener downwardly extending through the hole, and having a drive slot, a head, a shank, and a threaded region. The head is positioned within the bottom end. The head is separated from the threaded region by the shank. The fastener assembly comprises a cover disposed on the top end and having an access hole and top and bottom surfaces. The cover is welded to the sleeve to define an inner cavity between the cover, sleeve, and fastener head. The access hole is positioned over the drive slot. The cover, sleeve, and fastener comprises materials having high temperature, strength and oxidation resistances.

Abstract: A high temperature thermal protection systems for rockets, and associated methods, is disclosed. A representative system includes a launch vehicle having a first end and a second end generally opposite the first end. The launch vehicle is elongated along a vehicle axis extending between the first and second ends and carries a propulsion system having at least one nozzle positioned at the second end of the launch vehicle. A thermal protection apparatus positioned around the nozzle is used to provide cooling and/or insulation to the nozzle during the flight of the launch vehicle. The thermal protection apparatus can include multiple fabric layers and an insulation layer stacked and stitched together. The fabric layers can include metal alloy fibers. In representative systems, the thermal protection apparatus can further include provisions for water that saturates the insulation layer to provide further insulating and/or cooling effects.

Abstract: A high temperature thermal protection systems for rockets, and associated methods, is disclosed. A representative system includes a launch vehicle having a first end and a second end generally opposite the first end. The launch vehicle is elongated along a vehicle axis extending between the first and second ends and carries a propulsion system having at least one nozzle positioned at the second end of the launch vehicle. A thermal protection apparatus positioned around the nozzle is used to provide cooling and/or insulation to the nozzle during the flight of the launch vehicle. The thermal protection apparatus can include multiple fabric layers and an insulation layer stacked and stitched together. The fabric layers can include metal alloy fibers. In representative systems, the thermal protection apparatus can further include provisions for water that saturates the insulation layer to provide further insulating and/or cooling effects.

Abstract: A high temperature thermal protection systems for rockets, and associated methods, is disclosed. A representative system includes a launch vehicle having a first end and a second end generally opposite the first end. The launch vehicle is elongated along a vehicle axis extending between the first and second ends and carries a propulsion system having at least one nozzle positioned at the second end of the launch vehicle. A thermal protection apparatus positioned around the nozzle is used to provide cooling and/or insulation to the nozzle during the flight of the launch vehicle. The thermal protection apparatus can include multiple fabric layers and an insulation layer stacked and stitched together. The fabric layers can include metal alloy fibers. In representative systems, the thermal protection apparatus can further include provisions for water that saturates the insulation layer to provide further insulating and/or cooling effects.

Abstract: Disclosed are various embodiments for measuring a local permeability of a porous material. A probe can be positioned perpendicular to the surface of the material. The probe can be configured to sense a velocity of a fluid flowing over the surface. The probe can be positioned at a distance determined based on an average porosity of the material. The probe can take measurements at various positions at the distance by moving a minimum dimension between each measurement.

Abstract: Disclosed are various embodiments for measuring a local permeability of a porous material. A probe can be positioned perpendicular to the surface of the material. The probe can be configured to sense a velocity of a fluid flowing over the surface. The probe can be positioned at a distance determined based on an average porosity of the material. The probe can take measurements at various positions at the distance by moving a minimum dimension between each measurement.