5. Conclusion
Fatigue and overstress of the principal structural element are crucial
problems for all categories of aircraft. Light and Ultra-Light aircraft
have limited opportunities for the application of advanced Structural
Health Monitoring Systems. That is why the autonomous Surface Relief
Fatigue Indicator (SRFI) may be considered as a reliable tool for the
fatigue monitoring.
Light and Ultra-Light due to the action of the unallowable accelerations
in manoeuvers meet the overstress conditions for the components. The
excessive stresses can lead to the deformation of the structure, loss of
the aerodynamic characteristics and even to an aircraft crash. The
overstress can be revealed by the simple proposed device, called here
Overstress Indicator. It allows for prevention flight with damaged
structure, thus increases the safety of the operation.