A number of sealants are provided that are resistant to degradation by aircraft fluids. In some embodiments, the sealants are resistant to degradation by Jet A fluid and at least one of the three types of hydraulic fluids typically used in aircraft. These embodiments are also typically cure in place from a two-part polyurethane or polyurea mix, with cure to a visibly clear coating. In some embodiments, they may be sprayed on an aircraft surface or applied by hand (brush or injectable). In other of these embodiments, the sealants comprise, at least in part, a cured, soft, tacky polyurethane gel that is resistant to at least one of a synthetic hydrocarbon based or mineral oil based hydraulic fluid.

The present disclosure provides systems and methods for producing a hydrogen storage vessel that is lightweight. The hydrogen storage vessel may comprise an inner body and an outer body structured as concentric rings with a conic interface. The vessel may have four material layers, including a barrier layer, an insulation layer, a fiber knit, and an abrasion layer. The fiber knit may be braided to trap the hydrogen, as the barrier layer may not be completely impermeable. Additionally, the fiber braid may be clamped to the outer body, enabling pressure pushing on the inner body to wedge and seal the storage vessel.

A tank wall liner for a fuel tank includes a liner body made of a liner material. The liner material is a sealant or composite of sealant and fiber and/or textile materials. Multiple tank wall liners are installed on a tank wall and form a lining surface that seals the fuel in the tank from the tank skin. Also, a tank with the tank wall liner, an aircraft with a tank forming a portion of the fuselage, and methods of manufacturing the tank wall liner and the tank.

A tank wall liner for a fuel tank includes a liner body made of a liner material. The liner material is a sealant or composite of sealant and fiber and/or textile materials. Multiple tank wall liners are installed on a tank wall and form a lining surface that seals the fuel in the tank from the tank skin. Also, a tank with the tank wall liner, an aircraft with a tank forming a portion of the fuselage, and methods of manufacturing the tank wall liner and the tank.

The present invention relates to a curve-combined square pressure tank with which curves are combined so as to maintain internal high pressure, improve space efficiency, and reduce the weight thereof, and to a pressure tank, in which planes and curves are combined, formed by connecting flat plate members and curved members, having a plurality of aligned tension members for connecting the flat plate members facing each other, and having stress buffer parts formed at connection parts of the flat plate members and the curved members so as to enable internal pressure to be maintained.

A disclosed device allows a person to fly. A disclosed wearable flight system includes a plurality of propulsion assemblies including a left-hand propulsion assembly configured to be worn on a user's left hand and/or forearm and a right-hand propulsion assembly configured to be worn on a user's right hand and/or forearm. A further embodiment includes a body propulsion device that is configured to provide a net force along an axis defining a net body propulsion vector and a support device configured to support a user's waist or torso. The support device is configured to hold a user's body relative to the body propulsion device such that a line extending between center the of the user's head and the center of the user's waist extends, relative to the orientation of the net body propulsion vector during use, by a body propulsion elevation angle that is greater than zero.

A disclosed device allows a person to fly. A disclosed wearable flight system includes a plurality of propulsion assemblies including a left-hand propulsion assembly configured to be worn on a user's left hand and/or forearm and a right-hand propulsion assembly configured to be worn on a user's right hand and/or forearm. A further embodiment includes a body propulsion device that is configured to provide a net force along an axis defining a net body propulsion vector and a support device configured to support a user's waist or torso. The support device is configured to hold a user's body relative to the body propulsion device such that a line extending between center the of the user's head and the center of the user's waist extends, relative to the orientation of the net body propulsion vector during use, by a body propulsion elevation angle that is greater than zero.

Use of a hydrogen tank of a vehicle such as an aircraft for protecting at least one electrical connection device linked to at least one electrical device. At least one connection device is placed in a tank or in a sealed enclosure supplied with hydrogen by a tank or by any other source of hydrogen supply of the vehicle. The use of a tank that already exists in the vehicle makes it possible to avoid having to use specific chambers incorporated in a complex manner with the connection device.

Use of a hydrogen tank of a vehicle such as an aircraft for protecting at least one electrical connection device linked to at least one electrical device. At least one connection device is placed in a tank or in a sealed enclosure supplied with hydrogen by a tank or by any other source of hydrogen supply of the vehicle. The use of a tank that already exists in the vehicle makes it possible to avoid having to use specific chambers incorporated in a complex manner with the connection device.

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.