Fibre optic based sensors are becoming increasingly viable as replacements for traditionalflight test sensors. Here we present laboratory, wind tunnel and flight test results of fibreBragg gratings (FBG) used to measure surface strain and an extrinsic fibreFabry–Perotinterferometric (EFFPI) sensor used to measure unsteady pressure. The calibrated fullscale resolution and bandwidth of the FBG and EFFPI sensors were shown to be 0.29% at2.5 kHz up to 600 με and 0.15% at up to 10 kHz respectively up to 400 Pa. The wind tunneltests, completed on a 30% scale model, allowed the EFFPI sensor to be developed beforeincorporation with the FBG system into a Bulldog aerobatic light aircraft. The aircraft wasmodified and certified based on Certification Standards 23 (CS-23) and flight tested withsteady and dynamic manoeuvres. Aerobatic dynamic manoeuvres were performed in flightincluding a spin over a g-range −1g to +4g and demonstrated both the FBG and the EFFPIinstruments to have sufficient resolution to analyse the wing strain and fuselage unsteadypressure characteristics. The steady manoeuvres from the EFFPI sensor matched the windtunnel data to within experimental error while comparisons of the flight test and wind tunnelEFFPI results with a Kulite pressure sensor showed significant discrepancies between the twosets of data, greater than experimental error. This issue is discussed further in the paper.
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