INTRODUCTION: Hemorrhage is the leading cause of injury related pre-hospital mortality. We investigated worst case scenarios and possible requirements of Turkish Military. As we plan to use blood resources during casualty transport, the impact of transport related mechanical stress on PRBC (packed red blood cell) were analyzed. MATERIAL AND METHODS: The in vitro experiment was performed in the environmental test laboratories of ASELSAN(R). Operational vibrations of potential casualty transport mediums such as Sikorsky Helicopters, Kirpi(R) Armoured Vehicle and NATO vibration standardsoftware MIL-STD-810G were recorded. The most powerful mechanical stress, which was created by the NATO standard, was applied to 15 units of fresh (7 day) PRBC in a blood cooler box. The vibrations were simulated by TDS v895 Medium-Force Shaker Device. On site blood samples were analyzed at 0, 6th and 24th hours for biochemical and biomechanical analyses. RESULTS: The mean age of fresh and old PRBCs was 4.9 (SD +/- 2.2) and 32.8 (SD +/- 11.8) days, respectively. Six-hour mechanical damage of fresh PRBC was demonstrated by increased erythrocyte fragmentation rates (p=0.015), hemolysis rates (p=0.003), supernatant potassium levels (p=0.003) and decreased hematocrit levels (p=0.015). Old PRBC hemolysis rates (p=0.015), supernatant potassium levels (p=0.015), supernatant Hb (p=0.015) were increased and Htc levels were decreased (p=0.015) within 6 hours. Two (%13) units of fresh and none of the old PRBC were eligible for transfusion after 6 hours of mechanical stress. CONCLUSION: When the austere combat environment was simulated for 24 hours, fresh and old PRBC hemolysis rates were above the quality criteria. Currently, a technology to overcome this mechanical damage does not seem to exist. In the light of the above data, a new national project is being performed