I haven't been able to do this mission in the allotted time of 9:30 minutes. Just can't complete this mission in this short of time. Anyway, here's how you do the mission.
As soon as the mission starts, switch to your silenced pistol and run a few short steps in the direction of the guard patrolling by the nearby truck then DIVE to the ground. This causes him to stop and turn in your direction. Put a single shot right into his head. If you miss then fire a second shot into his head! You have to take this guy out without him making a sound.
Now, get up and run along the fence, behind the truck. Keep running near the fence all the way past the opening in the fence and back to where the back door of the far building is where the security camera is above the door. Walk to the side of that building and crouch. Lean around the building and look for the security camera to turn away from you. Then, crouchwalk up to the door and unlock it fast. Get inside the door. Crouchwalk up the the guard inside and pluck him with a single shot into the back of his head.
Go to the inside door and unlock it. Crouch walk up to the guard in the hallway and break his neck. Now.. Crouchwalk down the hallway to the last door on your left to the room with the computer. Lay flat by the side of the door. Open the door then immediately move off to the side so the guard inside won't see you when he turns and looks. Lean and look at the guard. Wait for him to turn back facing the wall again. Crawl in and pluck him in the back of his head.
Get up and run to the computer and use it. Now. Run all the way back out the same door you originally came in. As soon as you exit the door head quickly back around the building so the security camera won't see you long enough. Run to the fence and follow it all the way back around to where you started behind the truck in the lot. Now, crouchwalk up to the guard in the parking lot and use your knife to kill him. Crouchwalk to a position behind the guard standing near the guard shack. Crawl up behind him and break his neck. The guard inside the shack won't see you.
Crawl backwards a bit then crawl around the concrete barrier and under the horizontal gate-bar. Crawl to a position so you can see the guard inside the shack through the window. Use your binoculars to zoom in on his head. Then switch to your silenced pistol and pluck him straight through the window with a clean headshot. He goes down.
Get up and run outside the compound and along the fence to your right. Head down to the waterline and dive in. Swim along the dock and follow it all the way around to your right. Keep swimming and following the wall. Eventually you'll swim right past the airplane and over to a ladder along the wall near the crane. Climb that ladder slowly else the guard in the crane will turn and blast you.
When you finish climbing the ladder, immediately lay flat. Crawl to a position so you can get a clean shot at the guard on the stairs of the crane. Drill him by putting 2 shots into his back. Or, do a headshot if you can take it.
Now.. Get up and run right along the very edge of the dock near the water and head straight for the back fence with the gate. The sniper on the roof won't see you. When you get to the last tie-downs then crawl diagonally to your right and head straight for the control panel on the gate post. Here's the trick. Keep the pole with the control panel between you and the camera light. If you can't see the camera light then the camera can't see you!
When you reach the control panel, lean and wait for the camera to turn away from you. When it does, use the control panel quickly. When the fence gate opens up, stand and run right underneath the security camera and along the back fence. Run along the fence and all the way around to the far back fence. Crouch walk along the back fence and keep an eye on the guards patrolling the parking lot. When they start heading back towards the buildings, start moving again. Stay low and keep moving until you can get to the side of the building near the fence. Wait there and use your map computer to see when the guards start moving to the front of the buildings again. When they do, run along the fence a bit then head left straight for the rear of the small shack.
Crawl to the ladder. Be sure to CRAWL because you want to be laying flat when you exit the top of the ladder. Climb the ladder slowly else the guard on the inside second floor gets nervous. When you exit the top of the ladder you should be laying flat. Immediately crawl off to your left so you're not on the glass. Crouchwalk over behind the sniper. Either break his neck or pluck him with a clean headshot. Grab his grenade if he has one. Circle back to the glass skylight at the top of the ladder. Lean over to see if the guard below is looking at you. Don't use your heat-vision goggles to check on him else he hears you and looks upward. If he's not looking at you then crouch a bit near the glass so you can get a clean headshot through the sky light. Drill him straight through the top of his head. He collapses without a sound.
Now it gets tricky. Crouch onto the top of the skylight and take out your knife. Use it to break the glass underneath your feet and you'll fall through to the floor below. Crouchwalk into the room with the computer and use it. This deactivates the alarm for 2 minutes.
Now, crawl down the hallway. Use your heat vision goggles to get an idea where the guard nearest the stairs is standing. Put your goggles away then crawl up a bit. Lean upward to see where he is. Crawl forward a bit more. Lean upwards again. What you want to do is to just crawl to a spot where the very top of his head is just visible through the space in the flooring. You need to do a clean headshot on this guy but you can't crawl forward too far else he'll see you!
When you're in position, pluck him in the head. He goes down quietly. Him going down causes the other guard nearby him to run underneath the stairs right near you. So, quickly crouchwalk down the stairs and stay put on the landing area right there. Don't go all the way down those stairs else the guard will shoot you in the back! Stay there and wait for the guard underneath the stairs to start walking back to his normal position. When he does, drill him in the back with 3 shots or do a clean headshot if you feel lucky. Remember, if he makes any noise then the guards patrolling outside come running inside to investigate and all hell breaks loose.
Crouchwalk down the stairs and out the backdoor to where the generator is located. Activate the generator. Quickly crouchwalk back inside and go up the stairs to the second floor. You are going to jump out the second floor back window near the rear ladder. Crouch to that rear window and check your map computer first! You don't want to break the window when the patrolling guards are right there. When the guards aren't there, break the glass and crouch jump out the window down to the ground. You won't get hurt. Get up and RUN out of that area the exact same way you came in. Run straight out the gate and head directly to that crane.
At the bottom of the crane, toss all the stuff you're carrying onto the ground nearby. Hopefully, you've got a grenade to toss. Run up the stairs of the crane all the way to the top and activate the crane. The crane rotates and smashes a huge hole in the concrete wall into the final area.
Go down the crane stairs. Be sure to also toss the sniper rifle you picked up on the stairs. RUN STRAIGHT THROUGH THE OPENING AND TO YOUR LEFT! Keep running all the way around to the back door of the building there. You have to get into that building BEFORE the patrolling guards get to that side of the building where you are. Enter the back door of the building and walk through the open area into the room with the computer. Use the computer.
When the animation finishes, immediately use your knife to slice the guard standing right in front of you and then quickly dive straight into the water. You'll be right near the plane so you can swim to the ladder by the crane. Climb the ladder and pick up all the stuff you dropped nearby.
Now you have to take out White and his guards for the mission to end.
Enter through the hole in the fence again and go to your left. Crouch right there facing White and his guards. They won't see you. I had a grenade so I tossed it at White. The explosion took him and his guards out in a single blast. If you don't have a grenade then you have to snipe everybody one at a time.
Once you've killed White and his guards, the two guards in the back lot behind White's position will get excited. One will head your way. Snipe him quickly before he gets too close. Now snipe the last guard and you're done! Run and jump off the dock onto the wing of the plane and mission accomplished.
It's quicker and easier to kill White and his guards if you've managed to pick up a grenade along the way. Sometimes the sniper in the crane has one. Sometimes the sniper on the roof has one. Otherwise, you have to play cat-and-mouse to take all these people out without being seen. Find a grenade!
Tough mission! Cannot complete it in time so I haven't achieve David Jones status on this mission. Bummer! By the time I'm on the roof of the back building I've used 9:30.. Best I've done is 13:20. Anyway..