Reactive Armour

Reactive Armour

Reactive armor is a type of vehicle armor that reacts in some way to the impact of a weapon to reduce the damage done to the vehicle being protected. It is most effective in protecting against shaped charges and specially hardened long rod penetrators. The most common type is explosive reactive armor (ERA), but variants include self-limiting explosive reactive armor (SLERA), non-energetic reactive armor (NERA), non-explosive reactive armor (NxRA), and electric reactive armor. Unlike ERA and SLERA, NERA and NxRA modules can withstand multiple hits, but a second hit in exactly the same location will still penetrate.

Essentially all anti-tank munitions (with the exception of HESH) work by piercing the armor and killing the crew inside, disabling vital mechanical systems, or both. Reactive armor can be defeated with multiple hits in the same place, as by tandem-charge weapons, which fire two or more shaped charges in rapid succession. Without tandem charges, hitting the same spot twice is much more difficult.