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The angled crack problem has been given special attention in the recentyears by fracture mechanics investigators due to its close proximity to realistic conditionsin engineering structures. In this paper, an investigation of fatigue crack propagation insteel pipes containing an inclined surface crack is presented. The inclined angle of thecrack with respect to the axis of loading varied between 0o and 90o. A criterion based onthe shape of the crack tip plastic zone is proposed in the present study. The direction ofcrack initiation coincides with the direction of the minimum radius of the plastic zonedefined by the von Mises yield criterion. The threshold condition for non-growth of theinitial crack was established and assessed based on the experimental data.