Abstract: The capacitance type pressure transducer is disclosed which includes an isolation additional diaphragm made of the same material as the operative diaphragms the transducer. Material may be quartz, silicon, or aluminosilicate. The isolation diaphragm minimizes deflections of the operative diaphragms as the housing base is bowed due to the pressure differential between the internal reference pressure of the capsule and the ambient pressure. The transducer may be configured to measure an absolute pressure or a differential pressure.

Abstract: A combination air data probe performs a number of different pressure measurements from a single structure. Measurements of total pressure and total temperature are performed in an improved structural configuration which renders these measurements substantially insensitive to aircraft angle of attack. Static temperature is computed free of recovery factor error because of compensatory effects in the pressure and temperature signals. Another part of the probe provides measurement of static pressure and pressures for determining angle of attack.

Abstract: A dual capacitive pressure sensor includes matched variable capacitors which are immune to vibration and acceleration, but which respond equally to changes in external fluid pressure level. The structure of the sensor is configured to avoid calibration drift as the sensor ages, as well as to provide electrical shielding for the variable capacitors of the sensor.

Abstract: An air data sensor probe for providing measurements of total pressure, static pressure and angle-of-attack for an aircraft in flight. The probe is essentially cylindrical with a hemispherical nose. It has a vertically elongated central opening for measurement of total pressure and a plurality of off-axis openings, manifolded by pairs, to measure angle-of-attack. Static pressure is measured by a plurality of ports mounted back from the nose, manifolded together to provide the static pressure reading.

Abstract: A mechanical variable authority trim mixer for controlling the flow of fuel to an engine receives a main input from the throttle lever and a second input from a trim actuator motor. The trim mixer combines the inputs to produce a single output operably connected to the fuel metering control of the engine. A programmed cam modifies or neutralizes the effects of the trim input through selected ranges of the main throttle input stroke.