After you infiltrated his headquarters jet with the jet pack there is a sequence. When the game resumes you have to kill some opponents and Luther will tell you to put three bombs in the plane. On each side is a ladder. Go up one side then up the second ladder and go towards the back. There is a mark on the wall in red to plant one of the bombs. Hold Triangle to do so. Go down the two ladders and kill the guards that came in. Go to the other side then up the other two ladders. Again, there is a mark in red where you need to plant the second bomb. Come out and kill the other guards that entered. Go towards the back where you first came in to jet in the beginning of the level. Use your Micro-cord gun to latch on to the yellow pipe on the ceiling. Go all the way back and to find the third final bomb location. Plant it, then watch the intermission sequence. Stay there and take out your Sniper Pistol. Snipe the guards that are back by the blue crates. These opponents are tougher than the last ones you killed, but its easier to snipe them rather than killing them in close range. Then, get back to the door and go in. Kill the guard quietly and wait for the enemy to talk to you while you kill the guards that come down.