Air Data Attitude Heading Reference System The AD-AHRS (Air Data Attitude Heading Reference System) is a single LRU that provides outputs of air data and aircraft attitude. When combined with a separate magnetometer the unit will also output heading. When combined with a separate temperature probe, the unit will provide temperature and TAS outputs. The AD-AHRS incorporates pressure sensors, gyroscopes, and accelerometers, to calculate all air data and attitude information. The information is provided via a digital data bus to using systems. The unit incorporates all solid state components for exceptional reliability and accuracy.

Air Data Sensing Probes Pitot & Pitot-Static Probes. Pitot-static technology combines total and static pressure measurements in one probe. Optimal system configuration can be attained for any type of aircraft using pitot probes, pitot-static probes, multifunction probes (including flow angle measurements), integrated probe/transducer units, as well as air data systems, which consist of sensors, transducers and data transmission media. Air data probes provide vital information for aircraft flight and control. Pitot pressure, static pressure, local angle of attack pressures and angle of sideslip pressures are provided for calculating flight parameters that include pressure altitude, altitude rate, airspeed, Mach number, angle of attack and angle of sideslip.

• Aerodynamic compensation
• Deicing capabilities via self-regulating heaters
• Extremely high repeatability
• Refined pitot inlet designs that result from years of aerodynamic research
• Static pressure measurements taken outside of the aircraft boundary layer, which minimizes errors caused by fuselage deterioration and irregularities
• Materials and construction techniques that optimize strength, corrosion resistance, producibility and heat transfer

Engine Inlet Pressure Probes. [in process]

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Air Data Transducers & Computers Air data transducers and computers measure pneumatic pressures from pitot, pitot-static and static pressure ports with sensors and convert them to electrical signals. Air data transducers provide simple frequency or voltage outputs corresponding to different pressures. These outputs can be converted to digital signals and transmitted on data buses. Air data computers perform additional calculations and change the outputs from pressures to altitudes, airspeeds and Mach numbers. This data is typically transmitted on digital data busses such as Arinc 429, Mil-Std 1553B, RS422 and RS-485. Modular design provides low-cost customization for specific applications. Sensor Systems has a variety of sensor types that optimize cost and accuracy of the pressure measurements over flight envelopes ranging from lower-airspeed helicopters to high-flying supersonic jets.

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Angle of Attack & Stall Protection Angle of Attack Systems. Angle of attack (AOA) systems provide an economical means to achieve greater operational safety and efficiency for virtually any aircraft because they feature excellent accuracy and dynamic response. Because stall angle is constant (while stall velocity can vary considerably for a number of reasons), angle of attack is an ideal reference measurement for stall warning and/or stall prevention systems. Angle of attack is also a valuable reference measurement for realizing optimum performance during climb, cruise or landing. Pilots find angle of attack displays easy to relate to and simple to use. Sensor Systems has over 28 years of AOA production experience and over 18 years of resolver-based AOA experience. Over 45 aircraft AOA programs have been certified since 1970.

Angle of Attack Sensor. The company's Angle of Attack sensor is a swept vane design. The sensor contains two electrical, independent brushless resolvers (potentiometers are also available) and one viscous damper mechanically coupled to the vane. The sensor vane aligns itself with the local airflow, and the output expresses this position within specified accuracy parameters. The resolver and damper are driven at a ratio of 1:1 to the sensor vane. The vane heater is capable of deicing when in icing conditions, and the case heater evaporates moisture internal to the sensor.

Angle of Attack sensors provide:

• High reliability - up to four times longer than competitive products due to superior design, materials and testing
• Superior value - short lead time and low prices, plus low replacement frequency eliminates the need to buy and stock high quantities of spares
• Fast repair time - an average of 30 minutes compared to 3-4 hours for competitive sensors

Stall Protection System. A Stall Protection System (SPS) prevents the aircraft from attaining loss-of-control angle of attack conditions. Aircraft stall protection is performed in two stages. First, by sensing the angle of attack, the SPS alerts the pilot that the airplane is coming to a stall condition. Second, the activation of a shaker actuator shakes the elevator control column and simulates buffeting. If the pilot does not take corrective action and the angle of attack continues to increase, the SPS activates the stick pusher and moves the control column forward near its neutral position.

The SPS components form two subsystems. Each subsystem commands its associated control column shakers (pilot and copilot). The stick pusher is actuated only if both channels of the Stall Protection Computer (SPC) command the stick pusher. This logic is performed by a serial connection between the SPC channels. Each digital Stall Protection Computer Channel (SPCC) receives data from two independent angle of attack resolvers from its respective side and communicates with the other channel via a RS422 interface bus. Compensated angle of attack is then computed by averaging the resolver signals and checking subsystem validity of the opposite channel. This approach is taken in order to compensate the sideslip influence in alpha measurement.

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Current Monitor & Electronic Systems Brake Temperature Monitoring Systems. Overheated brakes affect performance and safety. For over 20 years, Sensor Systems has provided aircraft brake temperature sensing at the individual brake level. Sensors are available as thermocouple-based or platinum resistance-based units. Thermocouples are preferred for brake temperature sensing because they offer advantages related to temperature range, ruggedness and cost, along with fast response times. A basic four-channel brake temperature monitor receives a thermocouple signal from each of the four-brake thermocouple sensors and processes it to provide the required outputs. Outputs may include voltages or currents proportional to brake temperatures or a discrete warning output. Output information can be provided in an ARINC 429 format as well. Non-volatile memory in the monitor can be used to store trend data that is useful in pinpointing potential problems, such as brake drag.

To optimize safety, indicators alert pilots and crew of temperature problems. When a brake temperature exceeds a pre-determined temperature, a magnetic latching indicator changes from black to white. The indicator stays tripped, whether power is on or off, until the reset button on the monitor unit is pressed while powered. When over-temperature occurs, the monitoring unit illuminates an over-temperature annunciator light located on the flight deck panel. The light stays illuminated until the temperature falls below a pre-set temperature.

Current Monitors and Controllers. Sensor Systems offers heater monitoring capabilities that make pilots aware of current-to-heater system interruptions. Current monitors also control current so that sensor heater power use is limited when it is not needed, which increases sensor life and reliability. The Air Data Probe Heater Controller is capable of controlling (switching) and monitoring up to eight channels of either an AC or DC current-driven heater. The basic unit is populated only with the channel-specific components to control and monitor the actual number of channels required for a specific application.

A programmable logic device (PLD) controls the monitoring of each channel, the state of each discrete output, the monitoring of input discrete signals and the execution of self-tests. Each channel is monitored sequentially to obtain a voltage linearly proportional to the current. This analog value is converted into a digital representation and fed into the PLD, where it is compared to the threshold. Separate discrete outputs indicate when a specific heater channel fails, when any heater channel fails and when the heater current monitor fails.

Electronic Systems Junction Boxes. In order to reduce weight, space requirements and cost, Sensor Systems developed junction boxes. Junction boxes replace distributed terminal blocks and relay panels with a rack-mounted PCB-based system of interconnecting and switching. They centralize and combine wiring/system interconnections, relay panels (low power switching) and low power distribution functions. Junction boxes reduce significantly aircraft system modification and customization time and expense. Each junction box is housed in a 4MCU box with an ARINC 600 back connector and modular construction. An ARINC 600 connector connects via a rigid flexible circuit to a motherboard. A junction box may include up to five daughter boards, which contain socketed relays, a test point connector and other components.

Sensor Systems junction boxes are easy to service and maintain, which reduces maintenance time and related costs. Uniquely keyed boxes are easily removable, with uniquely keyed front cover and daughter boards. Socketed, daughter board-mounted relays can be replaced quickly. The easily accessible daughter board-mounted test connectors facilitate aircraft system fault diagnosis. Universal daughter boards are configurable to a variety of requirements.

Mass Flow Sensors. [in process]

Windshield Heater Controllers. Windshield heater controllers from Sensor Systems display consistently high performance and reliability. They are advanced and lightweight, which results from over 25 years of experience with heated device and controller design/production and superior product support. The latest designs include: High-performance technical design. Windshield heater controllers from Sensor Systems include state-of-the-art digital field-programmable gate array (FPGA) technology and communication standards. An FPGA-based design provides a device with digital performance without the certification hassles of a software-based design. A flexible configuration means that parameters can be configured to each unique application without hardware changes.

• Design family planning. The lowest total cost for windshield heater controllers can be provided through a family of flexible heater controllers. Aircraft to aircraft, the same controller baseline can be used for each individual program's requirements, which minimizes non-recurring costs. Features such as ARINC 429, serial communication and additional BIT can be added at no cost or low cost.
• Lower weight. The design concept results in units that are typically 15-20% lighter than the units they replace.

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Directional Surveying Equipment

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Surface Recording Gyro (SRG) For surveying and orienting with surface control and feedback, the Goodrich SRG is capable of mapping the direction of boreholes, or can be used for in-hole orientation of downhole packages (whipstocks, sensor, etc.) The system provides real time computer display of parametric coordinate X/Y/Z position tables, directional heading and graphs charting the direction upon completion of the survey.

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Flight Test Hardware The Model 0092BH or 0092BJ air data flight test boom accurately measures local static and pitot pressures, angles of attack, sideslip, and total temperature with the accuracy needed for precision flight test calibration use. These probes are ideally suited for aircraft, helicopters, drones, RPVs and other air vehicle programs. Models 0092BH and 0092BJ are nose or wing mounted and consist of a heated pitot-static tube, two flow angle sensors and an optional total temperature sensor. The flow angle and total temperature sensors are unheated, however, a 28 VDC or 115 VAC heater in the pitot-static portion of the unit allows for emergency operation during icing conditions. Rugged construction allows for use in extremely high vibration environments. This flight test hardware can be used in conjunction with the Goodrich 2014 Micro Air Data Computer to provide complete flight test air data.

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Heaters Structure Heater Systems. [in process]

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Ice Detection In-Flight Advisory and Primary Ice Detectors. Sensor Systems has produced ice detection systems since 1965 for use on more than 80 production aircraft programs. The systems attain a high degree of reliability by eliminating false icing signals and by utilizing extensive internal self-test/built-in-test and fault diagnostics. The ice detector detects ice accretion during aircraft flight and transmits an icing signal for remote display to the crew. The probe type ice detectors detect in all types of environmental icing conditions (including runback icing) for any aircraft surface, not just a single location.

The ice detectors consist of a sensing element that is exposed to the airstream. Ice builds up on this element when it is exposed to icing conditions. The ice buildup changes the element's mass. The mass change causes a shift in vibration frequency, which is measured by the ice detector's electronics. The electronics sends an icing signal when the frequency shift reaches a predetermined threshold. There are three ice detection options:

• Primary Automatic - the ice detector automatically activates ice protection systems at the optimal moment
• Primary Manual - the flight crew activates ice protection systems based on ice detector warnings
• Advisory - the crew activates the ice protection systems based on the standard flight manual criteria of outside temperature and the presence of moisture. The ice detector warning serves as back-up notification.

Primary ice detection systems deliver:

• Increased flight safety. Even when it is difficult for the crew to verify visible moisture, Sensor Systems primary ice detectors send timely warnings of icing conditions throughout the icing envelope. Timely ice detection reduces the risk of foreign object damage to the engines from the ingestion of large ice chunks.
• Reduced specific fuel consumption penalty. Operation of aircraft anti-icing/deicing systems consumes a significant amount of energy. Primary ice detection systems activate ice protection systems only when they are required.
• Reduced crew workload. Ice detection systems automatically signal the cockpit when icing conditions are encountered. The addition of an icing measurement system can reduce crew workload during those phases of flight when activity is highest and icing is most likely to occur.
• Prolonged aircraft deicing system life. The service life of the aircraft deicing system is extended because the system is operated only when icing conditions are present.

Icing Severity/Rate Sensing Systems. The latest icing systems (detectors plus controllers) from Sensor Systems are updated digital systems with discrete outputs. Developed in 1999 and 2000, the new digital systems with aspirated probes are designed primarily for helicopters. They give the flight crew indications of icing severity (light, moderate, severe) as well as liquid water content (LWC). Airspeed input from the air data computer and a temperature input from the outside air temperature sensor improve LWC accuracy over previous systems.

On-ground Wide Area Ice Detection Systems. The Sensor Systems IceHawk™ Wide Area Ice Detector was introduced in 1999 to address on-ground, pre-takeoff icing events. It is the only on-ground, wide-area ice detector approved by the FAA to replace a tactile inspection requirement. With the push of a button in any lighting conditions, the lightweight, portable IceHawk system scans the wide area of an aircraft surface with an infrared light beam. It detects ice by analyzing the polarization of the reflected signal. Wherever ice is present, the return infrared signal is unpolarized.

The scan instantly provides a color-coded video display of any and all frozen contaminants, including snow, frost, slush or ice, even in the presence of materials such as de/anti-icing fluid, hydraulic fluid and fuel. With the IceHawk system, the entire ice detection process takes just two seconds.

The IceHawk system offers these advantages:

• Fewer and faster icing decisions get aircraft in the air more quickly, which pleases passengers and airline management
• Elimination of unnecessary deicing reduces the use of glycol fluid, which helps the environment and saves money
• Better ice detection improves flight safety, which reduces risk

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Inertial and Attitude Sensors Goodrich Sensor Systems acquired Humphrey’s intertial systems and is now the world’s leading supplier of spinning mass gyroscopes, pendulums and magnetometers used in guidance and control systems and platform stabilization. These critical attitude measurements are used on a variety of high performance wheeled and tracked armored vehicles, aircraft, helicopters, missiles, drones and remotely piloted aerial vehicles. Goodrich Sensor Systems is committed to providing reliable sensing solutions focusing on affordability. Our commitment extends to an extensive family of inertial based products.

RG78 Series Rate Gyros: The RG78 series is the smallest rate gyro manufactured by Goodrich Sensor Systems. They can be used on virtually any applications requiring high accuracy and long service life. VG34 Series Vertical Gyro: The VG34 series is Goodrich’s smallest vertical gyro, providing accurate pitch and roll position data with infinite frequency response. FG40 Series Free Gyro: The Goodrich FG40 series of stored-energy free gyroscope models require virtually no power to operate, while providing exceptional shelf life. Useful flight data can be obtained for about three to ten minutes, making it a perfect application for ground and air launch missile programs. Other applications include sounding rockets and rocket sleds. FD01 Series Flux Detector: The FD01 series of flux detectors are a TSO certified, single-axis, gimbaled flux detector. This series can be used in most air vehicle applications requiring heading reference information. Pendulum Series: Goodrich’s low cost, precision, oil-damped pendulums give you a direct electrical reference to vertical and are used in hundreds of applications to control or record pitch and roll angle. VG38 Series Vertical Gyro: Ruggedized vertical gyro designed for use in tanks where severe environmental conditions exist. Resolver outputs on pitch and roll, failure monitoring system, and internally shock mounted. Four mounting positions may be adjusted by user. LA70 Series Accelerometers: Miniature, precision single and 3-axis potentiometric accelerometer. Requires low power and accepts AC or DC input voltage. Output is compatible with nearly all types of signal equipment. Ideal for torpedoes and oceanographic activities where size limitations are critical. FD31 Series Magnetometers: A miniature 3-axis strap down MIL Spec solid state magnetometer for use in magnetic heading systems. The magnetometer, together with a vertical gyro, provides accurate 3 axis information suitable for use in navigation computer systems to give direction as well as pitch and roll.

Directional Surveying Equipment product information

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Liquid Level Sensors Oil Level Sensors. Sensor Systems designs and builds capacitive sensors to measure engine oil tank level. The sensors self-compensate for variations in oil quality and the unique tank geometry. Because they are qualified to measure oil levels in the high temperature and high mechanical stress environment of an aircraft turbine engine, these sensors give years of uninterrupted service. Current sensors are qualified for operating temperatures between -55°C and +150°C. Oil level sensors operate on +12 to +32 VDC power, output high level analog signals and measure oil level within a pint.

Potable Water Level Sensors. Sensor Systems designs and manufactures two types of potable water level sensors: (1) Intrusive Ultrasonic. The intrusive water level sensor mounts on a flanged opening located at the top of the tank. An ultrasonic pulse is reflected off the water surface. Pulse time-of-flight is measured and the distance traveled is calculated using velocity of sound in air. Water volume is calculated using height of water and tank geometry. The sensor provides an output signal to a gauge on the flight attendant's panel, and it controls the fill valve on optional "pre-selection" systems. A pre-selection system allows operators to fill tanks to pre-selected quantities dictated by passenger load, which provides aircraft weight savings. Ultrasonic technology ensures: Non-contact measurement, which eliminates periodic maintenance Resistance to effects of freezing water High reliability because there are no moving parts High accuracy and stable, long-term performance Easy installation and no required calibration Pin-programmability for different tank sizes and configurations

(2) Non-intrusive Ultrasonic. The non-intrusive water level sensor mounts to the bottom of the water tank and transmits an ultrasonic pulse through the tank wall and water. The pulse reflects off the water/air surface and travels back to the transducer. Pulse time-of-flight, distance traveled and water volume are determined in the same ways as for the intrusive ultrasonic sensor. Non-intrusive sensing ensures: Improved accuracy (3 to 10 times higher than traditional capacitive sensing technologies) Stable, long term performance Improved reliability and maintainability Lower sensor and potable water system weight Reduced tank manufacturing costs Non-contact measurement, which does not require periodic cleaning Pin-programmability for different tank sizes and configurations

Waste Level Sensors. Sensor Systems designs and manufactures two types of waste level sensors: (1) Point level. Point level sensors are used in recirculating rinse toilets and vacuum waste management systems. In a recirculating rinse system, their primary function is to prevent overfilling of toilet tanks during ground servicing operations. A point level sensor detects fluid presence as a resistance change between two stainless steel probes. It sends a signal (analog or switched relay) to close the servicing shut-off valve, which prevents tank overfill. Point level sensors help to prevent "blue juice" overfills, which require cleanup and result in departure delays.

Waste tank overfill sensors are designed to eliminate overfill problems. This sensor detects the presence of blue tank pre-charge fluid or foam at a safe distance from the top of the tank, then provides a shut-off signal to the fill valve. It prevents blue liquid spills, the ingestion of blue foam into the aircraft venting, blower system and aft-bulkhead structure and lavatory odors. Preventing blue liquid contamination eliminates gate delays and costs associated with spill cleanup. Maintenance costs are reduced because aircraft repairs due to airframe corrosion and blower failures caused by blue liquid contamination are eliminated.

Point level sensors are also used in vacuum waste management system waste holding tanks to indicate a full tank condition.

(2) Continuous level. Continuous level sensors are used on vacuum toilet system-based aircraft. The stainless steel continuous level sensor provides highly accurate measurements using a temperature-corrected differential pressure measurement technique. The sensor computes the level of tank contents and sends an analog signal to the flight attendant's panel indicator. The sensor drives system status lights on the attendant's panel and service panel and reports system status to the maintenance computer. The sensor also controls a pre-charge valve for proper fill level and controls toilet operation by disabling toilet flushing when the tank is full.

Continuous level sensing ensures:

• Dependability - resulting from over 15 years of accurate, reliable operation
• Durability - stainless steel isolation diaphragms protect the solid state silicon sensor from damage
• Accuracy - wet-wet design prevents sensor ingestion of moisture from tank or vacuum lines

Sensor Systems is also in the process of developing and certifying a non-intrusive waste tank level sensor for use in vacuum and recirculating rinse systems.

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MEMS Sensor Systems designs, develops and produces micro electro-mechanical systems (MEMS) for high-performance sensors and actuators.

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Position Sensors Flap Position Transmitters. The flap position transmitter (FPT) is the primary input of flap position data for the flight command computer, cockpit indication system, ground proximity computer and several secondary functions. Mechanically linked to the flap actuation linkages, the FPT senses the position of the flap by measuring the rotary motion of the input shaft. An internally mounted case heater prevents moisture accumulation in the case. Moisture intrusion causes unpredictable, expensive corrosion and failure. The FPT consists of four major, modular assemblies that are designed for ease of troubleshooting and maintenance. Each unit is covered by a three-year warranty. FPTs provide: Increased MTBF - up to four times greater than existing FPTs, which slashes repair and replacement costs. Reduced FPT failure - eliminates up to 75 percent of failures, which means fewer flight delays and cancellations, and improves customer satisfaction. Reduced repair time - up to 50 percent less than existing units, which means that most repairs can be made simply and quickly, in about 30 minutes.

Tail Strike Proximity Sensors. As aircraft derivatives are stretched to allow for more passengers and more cargo, the increased weight increases risk of tail strike on takeoff. Tail strike proximity sensors measure the distance from the bottom of the aircraft tail to the ground. This measurement can be fed into the aircraft's flight controls to prevent the tail from striking the ground on takeoff. The sensor sends out a pulse of light, measures the time it takes the signal to return and calculates the distance from the sensor to the ground. Eventually, tail strike proximity sensors can be tied directly into the flight control system to provide computer-controlled optimization of takeoff rotation.

Tail strike proximity sensors provide these benefits:

• Eliminate damage to aircraft and related maintenance costs
• Allow airlines to increase takeoff weight on a fixed runway length
• Allow airlines to optimize rotation at takeoff and improve safety

Pressure Sensors and Transducers. FADEC Pressure Transducers. Peak turbine engine performance is achieved through the control of critical gas-path pressures. Standard pressure transducers (SDXs), designed and qualified by Sensors Systems, interface directly with FADECs (Full Authority Digital Engine Controllers). SDXs provide high-accuracy pressure data to improve engine-specific fuel consumption and enable active stall avoidance. By responding to bus control commands, an SDX outputs RS422-compatible data messages with 0.1% full-scale accuracy. With full-scale pressure ranges from 20 to 1000 PSIA, the accuracy of SDXs includes the effects of mechanical stresses and temperatures from -55°C to +125°C. With a mean time between failure of 166,000 hours, this robust design provides years of trouble-free operation. General Purpose Pressure Sensors. [in process]

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Smart Products SmartProbe™ air data systems combine probes and transducers in a single unit, which reduces line replaceable units (LRUs) and simplifies installation by removing the need for pneumatic plumbing between the probe and remote transducers. This approach results in reduced maintenance through the elimination of moisture traps, pressure leaks and leak testing requirements. SmartProbe™ systems provide a complete pneumatic measurement of airspeed, angle of attack and angle of sideslip in one unit with electronic output. SmartVane™ systems provide airspeed, angle of attack and angle of sideslip with electromechanical vanes that provide higher accuracy at lower airspeeds. SmartPort® systems provide a complete measurement of static pressure for altitude. Sensor Systems is the only company that provides a complete air data system using Smart products for the F-22 Raptor advanced fighter. Smart products are also used on the B-2 Spirit bomber and have been flown on the F-18.

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Speed Sensors

Engine Speed Sensors. Sensor Systems applies over 30 years of field experience to produce superior speed and torque sensors for turbine engines ranging from turbofans and turboprops to auxiliary power units and tail rotor torque systems.

Using proven materials and processes, multiple-coil speed sensors from Sensor Systems operate in severe temperature and vibration environments. Sensors offer a mean time between failure in excess of 300,000 hours. In addition, the company has extensive expertise in limited-access installation applications.

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Temperature Sensors Air Data Total Air Temperature Sensors. Total air temperature (TAT) measurement helps to determine critical flight parameters such as true airspeed computation, turbine engine control and static air temperature - factors that affect safety, economy and maximum performance. TAT sensors are also used for reference in wind tunnels and other ground test facilities. TAT sensor models are designed for use in a variety of altitude, weather, testing and turbine engine applications. In each sensor, a platinum or nickel resistance sensing element operates within a high-performance design that features superior flow separation and boundary layer control. Boundary layer control techniques allow anti-icing/deicing heat to be applied to the housing with minimal effect on accuracy. Superior accuracy and durability are achieved by:

• Aerodynamic boundary layer control
• Matching expansion coefficients of sensor components that eliminate stress at temperature extremes
• Materials and design that maximize heat transfer between measurement media and sensing element so that the sensing element comes quickly to equilibrium with the media
• Construction that eliminates strain on the sensing element
• Optional redundancy with two or three sensing elements

TAT sensors are available in deiced aspirated or non-aspirated styles. Aspirated sensors, which are offered only by Sensor Systems, prevent inaccurate pre-takeoff measurements. Plus, the company offers an open-wire sensing element that yields faster response times and higher accuracy.

Brake Temperature Sensors. The ability of an aircraft braking system to safely absorb the energy of an aborted take-off must be known prior to take-off. Brake temperature, the parameter most often used to measure this braking capacity, can be sensed with either a Platinum Resistance Thermometer (PRT) or a thermocouple.

Sensor Systems builds PRT and thermocouple temperature sensors for the dirty, high thermal/mechanical stress environment of an aircraft braking system. Thermocouples are generally lower priced, but they require special wiring and elaborate electronics. PRTs are more stable and require only standard wires and a simple bridge circuit.

Engine Exhaust Gas Temperature Sensors. Maximizing aircraft turbine engine performance can be aided by the accurate measurement of exhaust gas temperature (EGT). Sensor Systems manufactures EGT thermocouples known for their low price and rugged design for a wide variety of engines.

Engine Inlet Pressure & Temperature Probes. Turbine engine inlet pressure and total air temperature (TAT) are key engine control variables. Real-world flight conditions of accreting ice, foreign object debris and engine heat complicate accurate measurement of these parameters. Available with either single or dual temperature elements and an optional total pressure port, Sensor Systems P2T2 probes melt accumulated ice and prevent ice formation. Unique design characteristics ensure that engine or probe deicing heat does not affect sensor performance. These robust probes are qualified to withstand impact from damaging debris. Probe configurations protect sensing elements from abrading debris and provide years of uninterrupted service. Sensor Systems introduced the first MIL-P-27723E airframe-mounted TAT probe in 1956. The technology was extended to engine environments to sense P2 and T2. To keep pace with modern engine requirements, the company continues to advance sensor performance. Today, most aircraft power plants depend upon qualified Sensor Systems TAT or P2T2 probes to sense these critical control parameters.

Fuel & Oil Temperature Sensors. Sensor Systems manufactures a wide variety of fuel and oil temperature sensors. Platinum Resistance Thermometers (PRTs) and Nickel Resistance Temperature Detectors (RTDs) are used to measure a range of temperatures - from cryogenic rocket and turbine engine fuels to lubricating and hydraulic oils. These sensors exhibit a positive linear change in resistance over a temperature range of -269° to +1000°C, and they need only a simple bridge circuit to measure the resistance change. Fuel and oil temperature sensors accurately measure temperatures in extreme environments such as those found on space launch vehicles or aircraft propulsion systems. The company's temperature sensors perform to meet specific objectives or the cost advantage of an off-the-shelf MIL-T-7990 design.

Optical Flame Detectors. Dangerous fuel levels can accumulate within seconds of a turbine engine losing its ignition flame. Optical flame detectors from Sensor Systems sense and transmit a flameout condition, which alerts the engine control system to make critical adjustments. By transmitting an event within milliseconds, the ultra fast time response gives the control system time to adjust fuel flow and prevent a potentially catastrophic situation. Designed for ground turbine environments, optical flame detectors sense only the UV-NIR radiation of a natural gas combustion flame. By being insensitive to other radiation frequencies, the optical flame detector eliminates costly false signals. The optical flame detector is designed to provide years of uninterrupted service. Because it is capable of withstanding continuous exposure to +590°C, the flame detector sight tube can be mounted directly on the engine. An interconnecting cable rated to 350°C allows the electronics to be located in a benign location. Optical flame detectors typically interface directly with engine controllers. A unique signal strength meter provides health and cleanliness monitoring features.

Outside Air Temperature Sensors. [in process]

Space Vehicle Temperature Sensors. Sensor Systems manufactures surface Platinum Resistance Thermometers (PRTs) for satellites, scientific probes and manned space flight platforms. Often referred to as "patch sensors," PRTs exhibit a positive linear change in resistance over a temperature range of -269° to +1000°C and need only a simple bridge circuit to measure the resistance change.

Used in space since the 1960s, the company's wire wound platinum resistance sensors have demonstrated the reliability needed by the most critical applications. Screened to either MIL-T-23648B or ESA 4006 requirements, qualified PRTs are available for commercial satellites, NASA and ESA programs and the international space station.

Thermostats & Temperature Switches. Sensor Systems thermostats and temperature switches are designed to switch high currents and to operate in high vibration and shock environments. The snap action thermostats are hermetically sealed and capable of carrying up to a 7 amperes resistive load. The switches provide consistent performance at temperatures between -65°F and +550°F.

The thermostats are designed to provide fail-safe thermal protection of high-value critical flight components such as hydraulic, cabin heating, electronics cooling and deicing systems. Qualified thermostats and temperature switches provide exceptional reliability and long life. Standard configurations or custom packaging can meet most design requirements.

Turbine Blade Pyrometers. The thermal efficiency of a turbine engine is determined by the increase in combustion gas temperatures. By using turbine temperature as a control parameter, engines can be adjusted closer to their thermal limit than with other means. Turbine blade pyrometers can detect a specific temperature at a specific point on a turbine blade. Fuel flow can then be adjusted precisely to maximize engine performance. Additionally, by monitoring the temperature of each turbine blade, pending blade failure can be predicted. Sensor Systems manufactures turbine blade pyrometers for high performance aircraft engines. The highly stable design has undergone a comprehensive qualification program and is now in use on several U.S. Air Force aircraft. This non-contact sensing method has a measurement range of +1000°F to +2000°F. The unit mounts between the turbine case and bypass duct with provisions for fuel cooling to enhance reliability.

Lewis Engineering Temperature Sensors. In December 1999, Sensor Systems consolidated its temperature sensing production capabilities and the Lewis Engineering Company temperature sensor capabilities into the Eagan, Minnesota facility. Because the Lewis temperature sensors and capabilities were transferred in their entirety, the complete line of low-cost Lewis RTDs and thermocouple sensors is available.

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Temperature Standards

Standard Platinum Resistance Thermometer. ITS-90 (1990 International Temperature Standard) specifies Standard Platinum Resistance Thermometers (SPRTs) as the interpolative instruments for temperatures between the triple point of hydrogen (13.8033 K) and the freezing point of silver (1234.93K).

Being constructed with glass or quartz sheaths, most SPRT designs are fragile and susceptible to breakage. For a more robust design, Sensor Systems offers both Long Stem SPRTs and Capsule SPRTs with rugged metal sheaths. Although the initial cost of a 162CE metal sheath SPRT can be slightly higher than some glass or quartz sheath SPRTs, this small additional investment in a rugged sensor can pay for itself after just one unexpected bump. The 162CE is fabricated from fully annealed, high-purity platinum wire mounted in a strain-free fashion, and it offers unparalleled stability and low self-heating.


 

Windshield Wiper/Washer Systems Sensor Systems windshield wiper systems are an integral part of today's modern aircraft design. Wiper systems directly improve flight safety and efficiency by keeping the pilot's line of vision clear. Wiper systems clear rain, snow and debris from aircraft windshields in the most demanding flight and operating conditions. Wiper systems incorporate the most advanced technologies available today: Ultra-reliable brushless DC Motors and controls Low drag, aerodynamically shaped wiper arm and blade configurations Advanced high-strength and light-weight composite materials and alloys Motors and gearboxes that operate with low noise levels The company's wiper systems are custom engineered to meet the installation, operating and performance requirements unique to each aircraft application, from general aviation to commercial transport, including helicopters. Several types of standard off-the-shelf systems are available - integrated motor-converter units and motor-flexible-drive-converter systems - which can be easily tailored to meet a variety of needs.

Wiper systems offer the following options and operating features:

• Multiple operating speeds with intermittent delay cycle
• High output torque motor-converter units
• Outside-in or inside-out motor-converter unit mounting
• Low EMI motor controls
• Pilot and co-pilot system synchronization
• Off-pattern blade parking
• Blade lift-off ramps
• Replaceable rubber wiper blade elements
• "Dogleg" shape arms to maximize pilot visibility
• Washer systems that utilize fluid reservoir, pump and fluid dispensing arms and blades

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