The SAM Site automatically attacks enemy aerial vehicles by firing surface-to-air missiles with homing capabilities. They are extremely effective, capable of taking out an aircraft in several shots. The SAM site is always active, even if the power plant is destroyed.
In the campaign, SAM sites are typically targets for secondary objectives; taking them out allows for air support and reinforcements. SAM sites have extremely light armor, making them easy to destroy with a rocket launcher in a single shot or with a chain gun. They are often defended by a group of Nod soldiers with an officer nearby.