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When structures and components are submitted to multiaxial and variableamplitude loading, the damage accumulation process and the crack path under suchcomplex loading are not easy to predict. An original high cycle multiaxial fatigue lifeprediction method was proposed by Morel to account for some microplasticitymechanisms usually encountered in metallic materials at the scale of the grains. Theaim of this work is to study the conditions of damage accumulation and the orientationchange of the crack path when a variable amplitude sequence is composed of differentconstant amplitude loading blocks. More exactly, two different loading modes, torsionand tension, will be applied in the same sequence. The predictions of the critical planefatigue damage model are compared to fatigue tests under sequence of tension andtorsion carried out on a mild steel. Other data from the literature relative to sequenceof non similar load conditions (including multiaxial loading) are also analyzed.