Flight Demonstration Testing with Distributed Optical Fiber Sensor

This paper reports flight demonstration test results using an airborne structural health monitoring system with distributed optical fiber sensor. The test was conducted using a business jet in order to verify operability and feasibility of the airborne monitoring system. An optical fiber sensor was attached on the front spar of the vertical tail and the measurement device was on the cabin floor of the business jet. Dynamic strain and temperature changes during flights were measured and those values were close to those measured by strain gages and a thermocouple. Static distributed strain and temperature changes during flights were also measured and those values denoted the same tendency to those measured by the strain gages and the thermocouple. Despite the good results, there were some errors on temperature measurement results. The authors, therefore, developed a new installation method to decrease the temperature measurement errors. These developments mean that the operability and feasibility of our monitoring system in actual flights were verified.