The factory will begin to collapse as you enter the door so you are resorted to leave as fast as possible with the time limit on the left corner (varies with difficulty). As you escape, run to the right path when you reach the fork in the room where there will be a door on the far right wall. Continue through the building until you reach the area outside of the spiral staircase. You will need to activate the door to leave by striking the 3 floating orbs planted around which are located as follows: first is very close to the door you entered from, second is by the 4 silos, and the last one is beside a locked door that is glowing red. Now continue running to the room holding the airplane, just enter the plane and collect the rocket launcher inside. wait until you are allowed to leave, The plane will crash through the fan and your escape is to go through the fan blades lodged near the nose of the plane.