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In the present investigations a series of fatigue crack growth experimentshas been conducted using thin-walled, hollow cylinders with a notch made of fine-grained steel S460N. Pure tension-compression, pure torsion, proportional loadingresulting from these two load components and out-of-phase loading with phase anglesof 45° and 90° have been analyzed. Only constant amplitude loading with R=-1 hasbeen examined. Within the experiment the crack-initiation, the failure and the crackgrowth life as well as the crack growth curves and the crack paths have been identified.Depending on the loading type, two to four cracks initiate at different positions of thenotch. Each crack initiates as a corner crack on the inner side of the slot. Under puretension-compression and pure torsion the expected crack growth behavior can beobserved. Furthermore the crack growth behavior of specimens under proportional andout-of-phase loading with a phase angle of 45° are similar. Under out-of-phase loadingwith a phase angle of 90° various different types of crack initiation and growth havebeen identified. The crack-initiation correlates well with the local stresses and strains.Crack propagation lives vary with the type of loading.