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The phenomena of fatigue crack origination subsurface in slightly surfacesly-hardened specimens of titanium alloy VT3-1 (Ti-6Al-2Sn-4Zr-2Mo-0.1Si) has considered based on Acoustic Emission monitoring during specimen tests. It has shown that area of origin creation and short crack growth take place subsurface during unloading portion of cyclic loads. Crack path analysis based on fractograpnic consideration of several areas of origins has revealed that the twisting (or mode III crack opening) mechanism is dominant manner of material damage accumulation to create first facet of the origin area. Then, there is the short crack propagation around the first facet under combination of modes III and I crack opening to create fracture area. The introduced model of the subsurface material cracking because of twisting mechanism has discussed based on well-known results of numerical estimations of subsurface metals stress-state evolution during its plastic deformation on the meso-scale-level.