COINCIDENCE MASS SPECTROMETERS; ON-BOARD PERFORMANCE MONITORING AND RECORDING SYSTEMS FOR AIRCRAFT, INCLUDING DATA ENTRY PANELS, SUBMULTIPLEXERS AND SIGNAL CONDITIONERS IN SIGNAL PRECONDITIONER UNITS, MULTIPLEXER AND ANALOG-TO-DIGITAL CONVERTERS IN SIGNAL DATA TRANSLATORS, AND MAGNETIC TAPE RECORDERS; INSTRUMENTATION TAPE RECORDERS AND TAPE REPLAY TRANSPORTS; NUCLEAR AND NUCLEONIC QUANTITY GAUGES AND GAUGING SYSTEMS; ATMOSPHERIC ANALYSIS SYSTEMS; BIOMEDICAL DATA ACQUISITION SYSTEMS AND TAPE RECORDERS; STATIC AND DYNAMIC AIR PRESSURE TRANSDUCERS; ENGINE PRESSURE RATIO TRANSDUCERS AND INDICATING SYSTEMS; ENGINE ANALYZER SYSTEMS AND EXHAUST GAS TEMPERATURE INDICATORS; PROPULSION AREA PRESSURE RATIO TRANSDUCERS; AIR DISTANCE MEASURING TRANSDUCERS; AIRCRAFT INTEGRATED DATA SYSTEMS INCLUDING DATA ACQUISITION AND PROCESSING COMPONENTS COMPRISING SENSORS, TRANSDUCERS AND COMPUTERS FOR ACQUIRING, PROCESSING AND RECORDING DATA FROM AIRCRAFT ENGINES AND MAJOR AIRCRAFT SYSTEMS; CENTRAL AIR DATA SYSTEMS AND INSTRUMENTS FOR AIRCRAFT-NAMELY, AIR DATA COMPUTERS, ALTITUDE TRANSDUCERS, MACH TRANSDUCERS, BAROMETRIC ALTITUDE TRANSDUCERS AND CONTROLLERS, DIFFERENTIAL PRESSURE TRANSDUCERS, PRESSURE RATIO TRANSDUCERS, AIRSTREAM DIRECTION TRANSDUCERS, STATIC PRESSURE COMPENSATORS, TRUE AIR SPEED COMPUTING SYSTEMS, ANGLE OF ATTACK INDICATORS, ANGLE OF YAW INDICATORS, MACH INDICATORS, ALTIMETERS, AIR SPEED INDICATORS, TRUE AIR SPEED INDICATORS, SERVOED INDICATORS AND ELEVATION COMPUTERS; AUTOMATIC CONTROL MAIN VALVE UNITS FOR REGULATING THE AIR PRESSURE IN COMPARTMENTS OF AIRCRAFT, AND COMPONENT PARTS-NAMELY, ISOBARIC CHANGERS, CABIN ALTITUDE SELECTORS, RATE OF CHANGE SELECTORS, DIFFERENTIAL CHANGERS, DIFFERENTIAL TIMERS, JACK POSITIONED VALVES, VALVES OPERABLE AS AUXILIARY TO MAIN UNIT, PRESSURE RATIO CONTROL VALVES, DIFFERENTIAL PRESSURE CONTROL VALVES, DIFFERENTIAL RATE OF CHANGE CONTROL VALVES; MEASURING VENTURIS; HUMIDITY INDICATORS; THERMOSTATIC GOVERNORS; THERMOSTATIC TEMPERATURE CONTROL VALVES; PNEUMATIC, FLOATING CONTROL AND OIL DIVERTER THERMOSTATS; VARIABLE AIR FLOW, DIFFERENTIAL PRESSURE, AND FLOW MEASURING CONTROLS; PRESSURE BREATHING DEMAND REGULATORS; OIL TEMPERATURE REGULATORS; TEST INSTRUMENTS IN THE NATURE OF TEST STANDS AND TEST EQUIPMENT AND ANALYZERS FOR TESTING AND ANALYZING PERFORMANCE OF MECHANICAL, HYDRAULIC, PNEUMATIC, ELECTRICAL AND ELECTRONIC SYSTEMS UNDER SIMULATED OPERATIONAL CONDITIONS, FOR EXAMPLE, PNEUMATIC SIGNAL GENERATORS AND TEMPERATURE CONTROL TEST SETS; ELECTRONIC TEMPERATURE CONTROL SYSTEMS AND COMPONENTS FOR REGULATING TEMPERATURE OF AIRCRAFT COMPARTMENTS; AIRCRAFT WINDSHIELD TEMPERATURE CONTROLS; CONTROL SYSTEMS AND COMPONENTS FOR CONTROLLING AND REGULATING THE ENVIRONMENTAL PRESSURE AND TEMPERATURE IN SPACE SUITS AND SPACE CRAFT; CONTROL SYSTEMS AND COMPONENTS FOR CONTROLLING AND REGULATING THE FLOW OF CRYOGENIC FLUIDS FROM A CONTAINER SOURCE TO A POINT OF USE; AND PROCESS CONTROL COMPUTERS