Orbital Defense Generator Facility A-331

Summary
The Orbital Defense Stations around Reach are powered by large Orbital Defense Generator facilities. Facility A-331 is one of such facilities. It powered MAC Guns in orbit. The facitity was to be protected by the Spartan team arriving on Reach, but when the Covenant broke through the UNSC lines, the station was bombarded with heavy Plasma, and all Spartans and Marines guarding the facility are assumed dead.

There are at least seven reactor complexes. During The Battle of Reach, the Covenant comrpomised complex three, and the spartans fell back to complex seven. That is the last that was heard from them.