Under Platform
(Change vehicles) Be the first one on the map then choose a starfighter vehicle then fly around, looking for another vehicle. After you find one, try to make the vehicle fly under you. Once over the other vehicle, press enter/exit button to change vehicles. It can take a few tries.
(Turret Glitch) Go to either one of the Command buildings and jump into the turret. Aim the turret fully back and at an angle, the exact location is different for every turret watch this video for an example. Your character should now be able to walk through the seat of the Turret, when you achieve the right location thou, your character should fall through the ground.
(Extractor Glitch) To do this you need to be a Republic Jet Trooper now fly below the Extractor. The underside of the Extractor has no collidable walls but has a small platform at the bottom, so if you run out of jet pack fuel use this platform to refuel. When you have a full tank, fly up bellow the command post (don't fly through the floor you will go back up) position your self bellow one of the 6 pipes and slowly go up. Eventually, the Jet Trooper will glitch through the floor and you will be inside the pipes. Watch this video if you need a visual demonstration. Congratulations you cannot be killed unless the enemy uses the turrets on the Command buildings. To get out just fly though the pipe.