Application of Optical Fiber-Based Strain Sensing for the Full-Scale Static and Fatigue Tests of Aircraft Structure

An optical fiber-based Rayleigh backscattering distributed strain sensing system was adopted as the main structural integrity monitoring tool for airframe Full-Scale fatigue and ultimate tests. The strain signature along all major structural elements, as measured by the optical fibers, at each loading step was recorded and analyzed in real time. A specially developed human interface enabled easy tracking of emerging damage-related non-linear phenomena. This sensing concept reduces the need for adding hundreds of electrical strain gauges and eliminates intermediate conventional structural inspections during test, all leading to reducing test duration and cost.