The evacuation order for the South Tower was given around 8:57 a.m. by FDNY chiefs, who asked building personnel and a Port Authority police officer to evacuate the South Tower due to safety concerns after the North Tower was hit

. The second plane, United Airlines Flight 175, crashed into the South Tower at 9:03 a.m.

. Therefore, the time elapsed between the evacuation order for the South Tower and the crash of Flight 175 into the South Tower was approximately 6 minutes.