Abstract: A detection system in an aircraft includes an optical fiber arranged along a structure of the aircraft and affixed to the structure with clamps that are spaced apart along the structure. The optical fiber includes two or more sets of fiber Bragg gratings (FBGs). The system also includes a light source to generate light with two or more wavelengths for injection into the optical fiber, and processing circuitry to identify an overheat condition and monitor vibration experienced by the optical fiber based on reflected signals generated by the two or more sets of FBGs. Integrity of the clamps is indicated by monitoring the vibration.

Abstract: A method of operating an optical icing conditions sensor includes transmitting, with a transmitter, a light beam and thereby illuminating an illumination volume. A receiver array receives light over a range of receiving angles. The receiver array is configured to receive light having the wavelength over a receiver array field of view which overlaps with the illumination volume. A controller measures an intensity of light received by the receiver array. The controller determines that a cloud is present if the intensity is greater than a threshold value. The controller calculates scattering profile data of the light received by the receiver array if a cloud is determined to be present, which includes an angle of a scattering intensity peak within the range of receiving angles and a breadth of the scattering intensity peak. The controller estimates a representative droplet size within the cloud using the scattering profile data.

Abstract: A detection system in an aircraft includes an optical fiber arranged along a structure of the aircraft and affixed to the structure with clamps that are spaced apart along the structure. The optical fiber includes two or more sets of fiber Bragg gratings (FBGs). The system also includes a light source to generate light with two or more wavelengths for injection into the optical fiber, and processing circuitry to identify an overheat condition and monitor vibration experienced by the optical fiber based on reflected signals generated by the two or more sets of FBGs. Integrity of the clamps is indicated by monitoring the vibration.

Abstract: A system for an aircraft includes an optical sensor, at least one aircraft sensor, and a controller. The optical sensor is configured to emit a laser outside the aircraft, and the at least one aircraft sensor is configured to sense at least one aircraft condition. The controller is configured to determine a first operational state of the aircraft based upon the at least one aircraft condition and determine a second operational state of the aircraft based on the at least one aircraft condition, and operate the optical sensor to emit the laser at a first intensity during the first operational state and a second intensity during the second operational state, wherein the second intensity is greater than the first intensity.

Abstract: An air data sensor can include an acoustic transmitter configured to output an acoustic signal into an airflow and a plurality of acoustic transducers configured to receive the acoustic signal output by the acoustic transducer. The air data sensor can also include a light source configured to output a light beam into the airflow, and a light receiver configured to receive scattered light from the light beam. The light source and the light receiver can be bistatic such that a measurement zone is formed away from the air data sensor.

Abstract: Apparatus and associated methods relate to optically determining rotation frequency of a rotatable member using a Fabry-Perot cavity formed between a mirror and a movable reflective mirror. A cavity dimension between the mirror and a movable reflective mirror changes in response to movement of the movable reflective mirror. The movable reflective mirror is bonded to a magneto-strictive material having a thickness dimension that changes in response to changes in a magnetic field. A magnet generates the magnetic field, which changes in response to rotation of the rotatable member.

Abstract: A laser sensing system includes an emitter configured to emit a laser, and a controller. The intensity of the laser is based upon power provided to the laser sensing system. The controller is configured to control the power provided to the laser sensing system, obtain feedback parameters indicative in part of molecular content of the atmosphere, and control the power provided to the laser sensing system based upon the feedback parameters.

Abstract: A system includes a laser air data sensor and an acoustic air data sensor. The laser air data sensor is configured to emit directional light into airflow about an aircraft exterior and to generate first air data parameter outputs for the aircraft based on returns of the emitted directional light. The acoustic air data sensor is configured to emit acoustic signals into the airflow about the aircraft exterior, sense the acoustic signals, and generate second air data parameter outputs for the aircraft based on the sensed acoustic signals.

Abstract: An air data sensor can include an acoustic transmitter configured to output an acoustic signal into an airflow and a plurality of acoustic transducers configured to receive the acoustic signal output by the acoustic transducer. The air data sensor can also include a light source configured to output a light beam into the airflow, and a light receiver configured to receive scattered light from the light beam. The light source and the light receiver can be bistatic such that a measurement zone is formed away from the air data sensor.

Abstract: A system includes a laser air data sensor and an acoustic air data sensor. The laser air data sensor is configured to emit directional light into airflow about an aircraft exterior and to generate first air data parameter outputs for the aircraft based on returns of the emitted directional light. The acoustic air data sensor is configured to emit acoustic signals into the airflow about the aircraft exterior, sense the acoustic signals, and generate second air data parameter outputs for the aircraft based on the sensed acoustic signals.

Abstract: An air data probe includes a probe head, a port within the probe head in fluid communication with external airflow, and a pneumatic pressure sensor mounted within the port.

Abstract: An aircraft ice detection system is configured to determine a condition of a cloud and includes a radar transmitter, a radar receiver, optics and a splitter. The radar transmitter is configured to produce quasi-optical radiation. The optics are configured to direct the quasi-optical radiation from the radar transmitter to the cloud and receive reflected quasi-optical radiation from the cloud. The radar receiver is configured to receive the reflected quasi-optical radiation from the optics and the splitter is configured to direct the reflected quasi-optical radiation from the optics to the radar receiver.

Abstract: A system configured to monitor temperature in a plurality of zones of an aircraft includes an optical fiber with first and second ends, first and second connectors, and a first interrogator. The optical fiber includes a plurality of fiber Bragg gratings disposed in the optical fiber. The first connector is disposed on the first end of the optical fiber and the second connector is disposed on the second end of the optical fiber. The first interrogator is connected to the first connector and includes an optical switch. The optical switch is in optical communication with the first connector of the optical fiber and is configured to selectively block transmission of the optical signal to the optical fiber.

Abstract: A system configured to monitor a plurality of zones of an aircraft includes a line replaceable unit, a first interrogator, and a controller. The line replaceable unit includes first and second connectors in optical communication and an optical fiber. The optical fibers includes a first plurality of fiber Bragg gratings and a plurality of calibration fiber Bragg gratings in a pattern providing information related to a calibration value based upon a center wavelength of each of the first plurality of fiber Bragg gratings. The first interrogator is connected to the line replaceable unit at the first end of the optical fiber and is configured to provide a first optical signal and to receive a first optical response signal from the optical fiber. The controller is operatively connected to the first interrogator and is configured to determine the calibration value of the line replaceable unit.

Abstract: An aircraft ice detection system is configured to determine a condition of a cloud and includes a radar system, a lidar system, optics and a dichroic filter. The radar system is configured to project quasi-optical radiation to the cloud and receive reflected quasi-optical radiation from the cloud. The lidar system is configured to project optical radiation to the cloud and receive reflected optical radiation from the cloud. The optics are configured to direct the quasi-optical radiation and the optical radiation to the cloud and receive the reflected quasi-optical radiation and the reflected optical radiation from the cloud. The dichroic filter is configured to direct the quasi-optical radiation from the radar system to the optics, direct the optical radiation from the lidar system to the optics, direct the reflected quasi-optical radiation from the optics to the radar system and direct the reflected optical radiation from the optics to the lidar system.

Abstract: A method for detecting and determining a location of an overheat condition includes producing a narrowband optical signal with a laser source and optical pulse generator. The optical signal is sent into the optical fiber. A plurality of reflected optical signals is received. Reflection intensities are detected using a photodetector. The reflection intensities are compared with a triggering threshold. Response times of the reflected optical signals are recorded whenever the reflection intensity of the optical signals is greater than the triggering threshold. The narrowband optical signal is adjusted to another wavelength. An anomaly reflected optical signal is identified using a characteristic of the timings obtained through a range of wavelengths. The location of the overheat condition recorded response times is calculated. The location and existence of the overheat condition is communicated.

Abstract: An air data probe includes a probe head, a port within the probe head in fluid communication with external airflow, and a pneumatic pressure sensor mounted within the port.

Abstract: A system configured to a plurality of zones of an aircraft includes first and second connectors are in optical communication, an optical fiber, a first interrogator, and a controller. The optical fiber extends between the first and second connectors and includes a first timing fiber Bragg grating disposed in the optical fiber at a reference location of the optical fiber. The first interrogator is connected to the optical fiber and is configured to provide a first optical signal to the optical fiber and to receive a first timing signal from the optical fiber. The first timing fiber Bragg grating is configured to provide the first timing signal with information related to the first timing fiber Bragg grating from the first interrogator. The controller is operatively connected to the first interrogator and is configured to determine the reference location of the optical fiber.

Abstract: Apparatus and associated methods relate to projecting a light beam onto an interior surface of an aircraft window so as to indicate a testing location to test for ice accretion. The testing location is determined, by a boundary locator, based on aircraft flight conditions, aircraft exterior shape, and a predetermined size of super-cooled droplets, which could present a hazard to the aircraft. The determined test location corresponds to a calculated boundary that separates locations where super-cooled water droplets of the predetermined size cause ice-accretion from locations where such particles do not cause ice accretion, for such aircraft flight conditions. The light beam is then projected onto the interior surface of the aircraft window at the determined test location. The projected beam of light can indicate, to an observer and/or a detector, a location to monitor for ice accretion caused by super-cooled water droplets of the predetermined size.

Abstract: Overheat and fire detection for aircraft systems includes an optical controller and a fiber optic loop extending from the optical controller. The fiber optic loop extends through one or more zones of the aircraft. An optical signal is transmitted through the fiber optic loop from the optical controller and is also received back at the optical controller. The optical controller analyzes the optical signal to determine the temperature, strain, or both experienced within the zones.