A self-forming sealant system forms a seal between two parts or between a fastener and a part of a structure. In forming the seal, a first finish having a high surface energy is applied to the joint between the two parts or is applied to the fastener and the part. A second finish having a low surface energy is then applied adjacent to the area where the first finish was applied. A sealant is then applied to the joint between the two parts or the fastener and the part, where the sealant migrates to the joint or fastener coated with the first finish having the high surface energy and away from the areas adjacent the joint or the fastener coated by the second finish having the low surface energy.

Disclosed is a method of producing part of an airframe for attachment to a system. The method comprises: providing an initial structure; providing a reference structure; positioning the initial structure with respect to the reference structure such that its position/orientation relative to the reference structure is the same as the position/orientation relative to the system that it would have if the part of the airframe was attached to the system; specifying an inner mold line; applying, to an outer surface of the initial structure, material; and machining the material such that the position/orientation of the outer surface of the material with respect to the reference structure is the same as the position/orientation with respect to the system that the inner mold line would have if the part of the airframe was attached to the system.

Disclosed is a method of producing part of an airframe for attachment to a system. The method comprises: providing an initial structure; providing a reference structure; positioning the initial structure with respect to the reference structure such that its position/orientation relative to the reference structure is the same as the position/orientation relative to the system that it would have if the part of the airframe was attached to the system; specifying an inner mold line; applying, to an outer surface of the initial structure, material; and machining the material such that the position/orientation of the outer surface of the material with respect to the reference structure is the same as the position/orientation with respect to the system that the inner mold line would have if the part of the airframe was attached to the system.

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. In one embodiment, the sealant is used on a blade type aircraft antenna.

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. In one embodiment, the sealant is used on a blade type aircraft antenna.

This aircraft maintenance equipment is a fuel system leak test unit, designed to insure installation integrity of fuel system lines and hoses and to ensure that the system is free from any debris generated during the assembly and maintenance process for an aircraft. The unit is designed to check for leaks using vacuum or pressure while monitoring for fuel leaks or bubbles through a clear tube section.

This aircraft maintenance equipment is a fuel system leak test unit, designed to insure installation integrity of fuel system lines and hoses and to ensure that the system is free from any debris generated during the assembly and maintenance process for an aircraft. The unit is designed to check for leaks using vacuum or pressure while monitoring for fuel leaks or bubbles through a clear tube section.

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.

Provided are multi-tread vehicles and methods of operating such vehicles to access small interior spaces. A multi-tread vehicle may include two or more tread sections such that each pair of adjacent tread sections is interconnected by a connector section. Furthermore, each pair may have one or more degrees of articulations, such as being pivotable with respect to each other around one or more axis and/or being bendable with respect to each other around one or more axis. These articulation degrees may be provided by the connector section and/or by couplings between the connector section and each tread section. In some embodiments, each tread section may include two portions detachably coupled to each other. This detachable coupling may be used for disassembly of the multi-tread vehicle after or even during its use, for example, when only a portion of the vehicle needs to be retrieved from an interior space.

A system for controlling an environment within a fuel tank is provided. The system includes a conduit with a plurality of vents, wherein the conduit defines a path through the fuel tank, and wherein the conduit is configured to direct a flow of air along the path and out the plurality of vents.