Boosted gravity propulsion drive

Boosted Gravity Propulsion Drive is the boost that is put onto Covenant vehicles such as the Banshee, the Ghost, the Wraith, the Spectre and the Shadow on Halo 2 and Halo 3.The Boosted Bravity Propulsion Drive boosts the vehicle into the air, it is not currently known how this device makes the vehicle "levitate".