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Fastening holes are critical in the aircraft industry from a structuralintegrity viewpoint. This is because they act as stress concentrators from which cracksoften grow. In this work the image correlation technique has been used to measuredisplacements near a crack tip under mixed mode (I+II) stress field on Al 7010 samples.The crack tip position was deduced from the shape of the displacement fields. Thenanalytical displacement fields have been fitted to the experimental data by combiningMuskhelishvili's complex function approach with conformal mapping and multiple pointover-deterministic method to infer SIFs. The mode I experimentally calculated SIFsoverall agree well with the theoretical applied values, with the maximum difference lessthan 10%. The agreement for the mode II SIF was not as good as for mode I, althoughthe differences between calculated and nominal values are comparable to thoseobtained for mode I. Probably the signal to noise ratio is the main reason for thisdiscrepancy, as in all the cases nominal KI were several times bigger than KII.