Abstract: An optical-based fire detection system has a fire detecting mode in which the system is monitoring a flammable region for occurrence of fire in the flammable region and a system calibrating mode in which functionality of the system can be verified. The system comprises a light signal collecting unit located inside of the flammable region. The system also comprises a light signal processing unit located outside of the flammable region. The system further comprises a light signal calibrating unit located outside of the flammable region. The system also comprises one or more optical fiber bundles optically interconnecting the collecting unit, the processing unit, and the calibrating unit.

Abstract: An ignition suppressing enclosure configured to contain an ignition source is disclosed and includes a body portion defining an inner surface, an outer surface, and an enclosed volume containing a flammable gaseous mixture. The enclosed volume is sized to contain the ignition source. The enclosed volume of the ignition suppressing enclosure is surrounded by an exterior combustible environment also containing the flammable gaseous mixture. The ignition suppressing enclosure includes one or more vent paths that extend between the inner surface and the outer surface of the body portion, where each individual vent path includes an effective diameter based on at least a minimum ignition energy of the flammable gaseous mixture. The effective diameter of the individual vent path is selected to quench a flame that occurs within the enclosed volume of the ignition suppressing enclosure.

Abstract: An ignition suppressing enclosure configured to contain an ignition source is disclosed and includes a body portion defining an inner surface, an outer surface, and an enclosed volume containing a flammable gaseous mixture. The enclosed volume is sized to contain the ignition source. The enclosed volume of the ignition suppressing enclosure is surrounded by an exterior combustible environment also containing the flammable gaseous mixture. The ignition suppressing enclosure includes one or more vent paths that extend between the inner surface and the outer surface of the body portion, where each individual vent path includes an effective diameter based on at least a minimum ignition energy of the flammable gaseous mixture. The effective diameter of the individual vent path is selected to quench a flame that occurs within the enclosed volume of the ignition suppressing enclosure.

Abstract: A cover that extends over a fastener and methods of installing the cover over the fastener. The cover includes an open end positioned at a member from which the fastener extends. The cover also includes a closed end that extends over the fastener and shields the fastener from the exterior environment that can be combustible. A plurality of holes extend through the cover from the interior space to an exterior environment external to the cap.

Abstract: A cover that extends over a fastener and methods of installing the cover over the fastener. The cover includes an open end positioned at a member from which the fastener extends. The cover also includes a closed end that extends over the fastener and shields the fastener from the exterior environment that can be combustible. The cover includes an outer shell with one or more windows. An inner shell is positioned within the outer shell. The inner shell includes one or more windows that are offset from the windows of the outer shell. One or more flow paths extend through the windows for gas, liquid, and/or some particles to flow through the cover while removing the thermal and/or kinetic energy that may ignite the combustible exterior environment.

Abstract: A combustion test system includes a power source and a corona generator coupled to the power source. The combustion test system also includes a charge storage device. The charge storage device includes a charging surface spaced apart from the corona generator such that charge carriers, motivated by an electric field of the corona generator, intersect the charging surface to charge the charge storage device. The combustion test system also includes a first electrode coupled to the charge storage device and a second electrode coupled to a reference ground. The second electrode is spaced apart from the first electrode to produce an electrical arc between the first electrode and the second electrode based on a voltage difference between the first electrode and the second electrode.

Abstract: A cover that extends over a fastener and methods of installing the cover over the fastener. The cover includes an open end positioned at a member from which the fastener extends. The cover also includes a closed end that extends over the fastener and shields the fastener from the exterior environment that can be combustible. The cover includes an outer shell with one or more windows. An inner shell is positioned within the outer shell. The inner shell includes one or more windows that are offset from the windows of the outer shell. One or more flow paths extend through the windows for gas, liquid, and/or some particles to flow through the cover while removing the thermal and/or kinetic energy that may ignite the combustible exterior environment.

Abstract: A cover that extends over a fastener and methods of installing the cover over the fastener. The cover includes an open end positioned at a member from which the fastener extends. The cover also includes a closed end that extends over the fastener and shields the fastener from the exterior environment that can be combustible. A plurality of holes extend through the cover from the interior space to an exterior environment external to the cap.

Abstract: A combustion test system includes a power source and a corona generator coupled to the power source. The combustion test system also includes a charge storage device. The charge storage device includes a charging surface spaced apart from the corona generator such that charge carriers, motivated by an electric field of the corona generator, intersect the charging surface to charge the charge storage device. The combustion test system also includes a first electrode coupled to the charge storage device and a second electrode coupled to a reference ground. The second electrode is spaced apart from the first electrode to produce an electrical arc between the first electrode and the second electrode based on a voltage difference between the first electrode and the second electrode.

Abstract: Disclosed are ignition source testing systems and methods that utilize a foam with flammable components to indicate the presence of an ignition source on a test article (such as metallic components of a fuel system). Foam is applied to the test article and an energy discharge (such as a simulated lightning strike) is applied to the test article with the foam. The energy discharge may create an ignition source (such as an arc) on the test article that is sufficient to ignite the foam. Test methods comprise determining whether the foam ignited in response to the energy discharge. Test systems comprise the foam, the test article at least partially covered by the foam, and an energy source configured to discharge energy into the test article.

Abstract: Disclosed are ignition source testing systems and methods that utilize a foam with flammable components to indicate the presence of an ignition source on a test article (such as metallic components of a fuel system). Foam is applied to the test article and an energy discharge (such as a simulated lightning strike) is applied to the test article with the foam. The energy discharge may create an ignition source (such as an arc) on the test article that is sufficient to ignite the foam. Test methods comprise determining whether the foam ignited in response to the energy discharge. Test systems comprise the foam, the test article at least partially covered by the foam, and an energy source configured to discharge energy into the test article.

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: Systems and methods for ignition source testing with a flammable foam are disclosed. Flammable foam systems and methods for testing use a flammable foam that includes fuel and oxidant. Flammable foam is applied to a test article and an energy discharge is applied to the test article. Methods include determining whether the flammable foam ignited in response to the energy discharge.

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: Systems and methods for ignition source testing with a flammable foam are disclosed. Flammable foam systems and methods for testing use a flammable foam that includes fuel and oxidant. Flammable foam is applied to a test article and an energy discharge is applied to the test article. Methods include determining whether the flammable foam ignited in response to the energy discharge.