ALTITUDE 2,000 FEET, FLIGHT SPEED 207 KPH

Absolute pressure sensors are crucial to measuring a helicopter’s altitude and flight speed. And Thales has developed a new sensor that offers revolutionary precision of 0.05% no matter what you throw at it. The sensor’s performance even stands up to the vibrations, landing impacts, intense accelerations, and extreme temperature fluctuations (from -40°C to 200°C) found on board your average helicopter.

Technology

Leti’s all-silicon pressure sensors replaced the bulkier, less-reliable metal-membrane sensors traditionally used. The Leti sensors are made from crystalline silicon, offering excellent mechanical performance and enhanced temperature stability.

The detection principle used was improved to meet the performance and temperature-resistance requirements of the target application. Piezoresistive strain gauges on an insulator were used to measure the deformation of a membrane, one side of which was exposed to a reference pressure level. The gauges are engraved on SOI (silicon-oninsulator). The silicon oxide layer located under the gauges prevents leakage current, which enhances the device’s temperature stability.

This absolute pressure sensor was successfully tested for use in aerospace applications. First developed in 1998, the sensor today continues to offer the best performance on the market.