Tank jumping

First you need to get the Tank flipped by driving it up a corner of a building. Then get to the highest point of the tank tracks and run down them. Once your at the bottom, flip the tank and you will go flying. (The side of the tank that you go on is different on some levels)

Double Tank Jumping
First you need two people for this glitch, you need to get a Tank and flip it by driving it up a courner of a building. then get the other person to drive a second Tank on top of the first then they stay inside of the tank, the first person then flips the first Tank sending the the first person, the second person and the second Tank flying.