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Experimental results were obtained from fatigue tests of thin-walled7075-T6 aluminium tube specimens with a circular transverse hole. The loadingconditions included pure axial, pure torsion, and combined in-phase and out-of-phasetests. Tests were also conducted under axial loading with intermittent torsion cycles.Macro-cracks grew along the maximum principal plane direction (i.e. mode I crackgrowth). In out-of-phase tests crack branching occurred with a torturous crack path,resulting in a lower crack growth rate compared to in-phase loading, attributed torepeated bifurcation at the crack tip. Intermittent torsion cycles decreased fatigue lifeand accelerated axial crack growth rate, with the effect increasing with increasednumber of applied torsion cycles.