When Hawk blows up the truck, turn right and go through the double doors directly back into the building. Watch for windows and snipers on 2 nd story ledges. Go upstairs to the balcony. Follow the hallway around to the guard tower. Pick up grenades, med kits, armor, and C4, and go back to the door with the red light above it, near the staircase.
First target is a worker.
As you walk down hallway, three enemies in room will attack. Hawk opens up the hanger door, but triggers the alarm. There's an Emergency Medical Station in far corner of the room, plus one grenade and one flash pak. Kill alerted guards along the way. When you exit the building, a dog and two guards will attack.