Available in
The Final Test (Tutorial) Mission.
From the beginning, you'll want to go to the right hand side, hop the fence, and go into the window behind the enemy without alerting him. Once inside follow the right hand side door, and pick up the wrench. Continue to the next room to find the
Mechanic disguise.
Now interact with the plane in the hangar to sabotage it; watch out for the other mechanic who may be suspicious of you. Upon completing that, go upstairs to find the target; Jasper Knight, and talk to him. He will follow you to the plane where you pick up the clipboard nearby and take him through safety protocol. Keep telling him what to do until he ejects and then escape the area.