From Sonic Retro
The Jet Booster is an upgrade available to E-102 "γ" in Sonic Adventure. Presumably designed by Dr. Robotnik, this mechanical plate allows Gamma to float serenely downwards while dropping rather than plummet like the 825.256kg titanium brick that he is. All the other E-100 Series robots in Adventure have their own Jet Boosters when Gamma fights them (except Zeta, for obvious reasons).
- Purpose: Lets Gamma float while descending by holding down the button.
- Location: Egg Carrier Adventure Field, main hall, armoury (through a door on the upper floor).
- Requirements: None, although Eggman doesn't open the armoury for you until after you've freed Amy from her cell.
- Required For: Nothing, but the lift pod doesn't descend to get you out of the Main Hall until you pick it up.