Abstract: An apparatus and a method for simulating a mechanical stress applied to a sealant from a lightning strike upon an aircraft is provided. The apparatus comprises a specimen, a test fixture, and a capacitor. The specimen comprises an electrically non-conductive sealant for an aircraft fuel tank having a cylindrical shape, and an electrically conductive wire centered axially within the sealant. The test fixture secures the specimen during testing. The capacitor is electrically coupled to the test fixture, and simulates a lightning strike upon the aircraft by vaporizing the wire with a current to generate a mechanical shock to the sealant.

Abstract: Methods and systems for duct protection of a vehicle are provided. The methods and systems provided include an apparatus for containing a flow of fluid discharged from a fracture in a duct. The apparatus includes a ballistic containment layer and an insulation sheath coupled to the ballistic containment layer. The insulation sheath includes a first air containment layer, an insulation layer, and a second air containment layer.

Abstract: A bond inspection system may include a material that reacts to applied activation energy by creating a compression wave, the material positioned adjacent a surface of a structure having a bond to be inspected and shaped in a predetermined pattern, such that reaction of the material causes compression waves to travel through the surface and structure; a source of activation energy capable of directing the activation energy at the material; and a controller programmed to actuate the source of activation energy to direct the activation energy at discrete portions of the predetermined pattern of material in a predetermined sequence selected to create a plurality of the compression waves so that the compression waves reflect from an opposite side of the structure as a plurality of tension waves that combine at substantially the same time at a bondline of the structure to be inspected.

Abstract: A system and methods are provided for evaluating a bond between structures. The system includes an assembly of at least two bonded structures. The assembly has a front surface, a back surface, a thickness, and a bond disposed between the front surface and the back surface. At least one delay component is attached to the front surface of the assembly having a body having a front face, a back face, and a thickness. The system further includes a laser source capable of depositing laser energy onto a front face of the delay component, where a first portion of the laser energy is absorbed by the front face of the delay component to generate a first compression wave that propagates through the body of the delay component. A second portion of the laser energy is absorbed by the back face of the component to generate a second compression wave that reflects off of the back surface of the assembly to produce a tensile wave that stresses the bond.

Abstract: Embodiments described herein provide apparatus and a method for simulating a mechanical stress applied to a sealant from a lightning strike upon an aircraft. One embodiment comprises a specimen, a test fixture, and a capacitor. The specimen comprises an electrically non-conductive sealant for an aircraft fuel tank having a cylindrical shape, and an electrically conductive wire centered axially within the sealant. The test fixture secures the specimen during testing. The capacitor is electrically coupled to the test fixture, and simulates a lightning strike upon the aircraft by vaporizing the wire with a current to generate a mechanical shock to the sealant.

Abstract: Methods and systems for duct protection of a vehicle are provided. The methods and systems provided include an apparatus for containing a flow of fluid discharged from a fracture in a duct. The apparatus includes a ballistic containment layer and an insulation sheath coupled to the ballistic containment layer. The insulation sheath includes a first air containment layer, an insulation layer, and a second air containment layer.

Abstract: A bond inspection system may include a material that reacts to applied activation energy by creating a compression wave, the material positioned adjacent a surface of a structure having a bond to be inspected and shaped in a predetermined pattern, such that reaction of the material causes compression waves to travel through the surface and structure; a source of activation energy capable of directing the activation energy at the material; and a controller programmed to actuate the source of activation energy to direct the activation energy at discrete portions of the predetermined pattern of material in a predetermined sequence selected to create a plurality of the compression waves so that the compression waves reflect from an opposite side of the structure as a plurality of tension waves that combine at substantially the same time at a bondline of the structure to be inspected.

Abstract: A system and methods are provided for evaluating a bond between structures. The system includes an assembly of at least two bonded structures. The assembly has a front surface, a back surface, a thickness, and a bond disposed between the front surface and the back surface. At least one delay component is attached to the front surface of the assembly having a body having a front face, a back face, and a thickness. The system further includes a laser source capable of depositing laser energy onto a front face of the delay component, where a first portion of the laser energy is absorbed by the front face of the delay component to generate a first compression wave that propagates through the body of the delay component. A second portion of the laser energy is absorbed by the back face of the component to generate a second compression wave that reflects off of the back surface of the assembly to produce a tensile wave that stresses the bond.

Abstract: A method and apparatus for testing a bond interface is provided. An initial wave is transmitted into a first end of a first material. The first material is connected to a second material by an adhesive at a bond interface. The first material is dissimilar to the second material. The initial wave splits into a first wave and a second wave at the bond interface. Parameters are changed so a first wave travels through the first material to the first end of the first material and back to the bond interface in a first amount of time and the second wave travels through the second material to a second end of the second material and back to the bond interface in a second amount of time. The first amount of time is substantially equal to the second amount of time. A tension is obtained in the adhesive at the bond interface.

Abstract: Exemplary embodiments are disclosed for the use of Lamb waves in laser bond inspection.

Abstract: An impact test system for collecting hail storm data comprises a vehicle, a video recorder, a container, a plurality of dynamic force sensors, an atmospheric instrument system, a mounting fixture, and a data processing system. The plurality of dynamic force sensors is capable of detecting force generated by an impact of an object. The plurality of markers is capable of being used to determine an orientation of an incoming object. The mounting fixture is capable of holding a test specimen. The data processing system is capable of collecting data from the plurality of dynamic force sensors, the atmospheric instrument system, and the video recorder.

Abstract: Methods, systems, and apparatuses are provided for generation of focused stress waves that selectively apply tensile stress to local regions of a bonded article.

Abstract: An impact test system for collecting hail storm data comprises a vehicle, a video recorder, a container, a plurality of dynamic force sensors, an atmospheric instrument system, a mounting fixture, and a data processing system. The plurality of dynamic force sensors is capable of detecting force generated by an impact of an object. The plurality of markers is capable of being used to determine an orientation of an incoming object. The mounting fixture is capable of holding a test specimen. The data processing system is capable of collecting data from the plurality of dynamic force sensors, the atmospheric instrument system, and the video recorder.

Abstract: A system and method for non-destructively testing the strength of bonded joints, particularly a bonded joint between two composite components, is provided. The method generally includes activating a source of rapid surface pressure application against a bonded assembly containing the bonded joint to create a shock load. The resulting shock load first generates compression and then tension within the bonded joint, along with surface motions proximate the bonded assembly, and a surface motion detector measures the surface motions to determine the minimum strength of the bonded joint. Accordingly, the surface motions are correlated to the strength of the bonded joint. Further, the magnitude of the impact may be adjusted to vary the amount of tension within the bonded joint to correspond with various load conditions.

Abstract: A system and method for non-destructively testing the strength of bonded joints, particularly a bonded joint between two composite components, is provided. The method generally comprises activating a source of rapid surface pressure application against a bonded assembly containing the bonded joint to create a shock load. The resulting shock load first generates compression and then tension within the bonded joint, along with surface motions proximate the bonded assembly, and a surface motion detector measures the surface motions to determine the minimum strength of the bonded joint. Accordingly, the surface motions are correlated to the strength of the bonded joint. Further, the magnitude of the impact may be adjusted to vary the amount of tension within the bonded joint to correspond with various load conditions.