Engineering topics
Publications and source records attributed to Wilson, E. J..
Capacitive strain gage and signal conditioning system measures stress-induced strain and cancels thermal expansion strain at temperatures to 1,500 F (815 C). Gage does not significantly restrain or reinforce specimen.
A flight-loads measurement program on the YF-12 aircraft required the mounting of 101 strain-gauge bridges in the fuselage, fuel tanks, control surfaces, and three stations on the left wing. The sensors were to be installed primarily on titanium and were required to operate between -70 and +600 F. Strain gauges with modified Karma filaments and backings of glass-fiber reinforced epoxy resin matrices were selected and were installed with an epoxy adhesive. Attention is given to the calibration, mounting, and performance of the sensors in flight-load measurements.
An experimental program was conducted to extend the Tracor Safety Gauge (patent pending) to elevated temperature service. The Safety Gauge is based on a conductive composite device which can be fabricated to function as a fatigue sensor that undergoes an irreversible resistance increase which results from cumulative strain damage. Prototype sensors were developed which appear capable of 1000 deg F operation for short periods of time (approaching one hour); however, bonding difficulties currently limit their use to about 775 deg F. The resistance change of the sensor was generally on the order of 400% or greater as the fatigue life of a titanium alloy (Ti-5Al-2.5Sn) test specimen was approached.
Aircraft flight load measurements in high temperature environment, determining optimal strain gage installation and calibration
Bonded and weldable strain gages for aircraft flight loads measurements at high temperatures, discussing installation, calibration and performance tests
High temperature thermal null strain gage with sensing unit and electronic control unit to measure mechanical strain in terms of induced thermal strain
Strain gages to measure flight loads in high temperature environment, discussing selection, calibration techniques and performance characteristics