THIS PROJECT AIMS AT DEVELOPING A HIGHLY ACCURATE AND ECONOMICAL AIRCRAFT ALTIMETER.

THIS PROJECT AIMS AT DEVELOPING A HIGHLY ACCURATE AND ECONOMICAL AIRCRAFT ALTIMETER. THE MOTION OF AN EVACUATED BELLOWS WILL BE MONITORED BY AN OPTICAL POSITION SENSOR WHICH WILL GIVE AN ELECTRICAL ANALOG SIGNAL LINEARLY RELATED TO THE ATMOSPHERIC PRESSURE. WHILE THE SENSOR IS VERY SMALL, RUGGED AND INEXPENSIVE, IT HAS A LARGE DYNAMIC RANGE (100,000), HIGH LINEARITY (0.01%) AND HIGH SENSITIVITY (MAXIMUM BELLOWS WALL DISPLACEMENT NEEDED: 0.0014 INCHES). IMPORTANT ADVANTAGES ARE FORESEEN IN THIS NEW ALTIMETER CONCEPT: THE ERRORS AND THE LIMITED RESOLUTION INHERENT IN THE COMPLEX MECHANICAL SYSTEM OF A MECHANICAL ALTIMETER ARE AVOIDED; NOTHING DISTURBS THE BELLOWS EXCEPT FOR A LIGHT BEAM; ZERO SETTING, BAROMETRIC PRESSURE CORRECTION AND CALIBRATION CAN ALL BE DONE ELECTRONICALLY; ITS ELECTRICAL SIGNAL IS DIRECTLY COMPATIBLE WITH DIGITAL DISPLAY, COMPUTER INTERFACE AND AUTOMATIC ALTITUDE TRANSMISSION, AND FINALLY, ITS SIMPLICITY OF DESIGN SHOULD LEAD TO HIGH RELIABILITY.