Spaced armor basically works by detonating the projectile before it hits the main armor and disipating its effects. Most AT rounds are shaped charge projectiles that detonate and form a small jet of molten copper (or other metal) that cuts through the armor, think RPG. The space that is provided dissipates the jet and defeats or lessens its effects. It is very effective at defeating them and making them ineffective. A vehicle with spaced armor is more effective against shaped charge projectiles than just solid rolled steel.
Gino P. Quintiliani
Field Artillery --- The KING of BATTLE!!!