Early Banshee

It is possible to fly a Covenant Banshee in Assault on the Control Room (Level). First of all, make sure you have both the Sniper Rifle & the Rocket Launcher. Then, when you reach the area where the Scorpion tank is, finish off all of the Covenant forces. After clearing the area of all hostiles, leave the Scorpion alone, or get out of it if you used it in the clearing effort. Next, you'll want to avoid the tunnel, instead, walk down the small hill & look up while doing so. You should then notice a small rock bridge followed by a small platform coming out from the canyon wall. Keep walking, slowly, until you get a perfectly clear view of the platform. Take out your Sniper Rifle, zoom in all the way, & try to aim at the middle part of the platform. Then, without moving, switch to your Rocket Launcher & fire. The end result (if your aim was perfect): the Banshee that would've been used against you by a Covenant Elite should tumble to the canyon floor. This may take a few tries & some re-aiming, but this can work. You can actually use the Banshee, so have a blast & take advantage of a time saving hint later on. This trick can really come in handy in a CO-OP Campaign, just imagine this: Your buddy + 4 Marines in the Scorpion, and you in the Banshee providing air support (or vice-versa).

This trick can also be a great headache saver. When you get to the second canyon, fly the Banshee over that towering rock building in the middle. Then, just keep flying very high until you get to those twin bridges, land on the second bridge (the one further from you on approach). Simply go through the doors, but make sure the arrows are pointing the right way. The end result: you can finish the level with no more Covenant forces to deal with.

Another way to do this is near the end of the level when Cortana says how odd and subtle the control room looks. Before here get the Active Camouflage and charge through, towards a Banshee. This saves you from having to kill all the Covenant surrounding the control room, and you can have additional firepower on your way to the room itself.