Low-Cost Vertical Accelerometer For Aircraft

Self-aligning device measures vertical acceleration of aircraft but costs only small fraction of price of full inertial navigation system. Consists of accelerometer mounted vertically on inner gimbal of artificial horizon. Vertical accelerometer proves to be effective aid to Global Positioning System (GPS) navigation receivers in general-aviation aircraft and helicopters. Low-cost vertical accelerometer used to improve on vertical accuracy and reliability of GPS receiver alone. Also used to improve altitude accuracy for aircraft otherwise equipped with only baro-altimeter for altitude measurement.