text: Chapter 3
  sustainment group performs repairs and returns components and end-items to their supported units, or to the
  supply system through the National Maintenance Program.
  3-80. When deployed, the theater aviation maintenance sustainment group is attached to the joint force
  sustainment headquarters or expeditionary sustainment command and sets up at a secure location in an AO.
  It establishes and provides 24-hour, fixed-base aviation field and sustainment maintenance, logistics, and
  other essential aviation sustainment support to aviation units. The theater aviation maintenance sustainment
  group performs field maintenance, depot-level crash and battle damage repair, and sustainment and
  depot-level repair of major end items. It also performs sustainment-level maintenance for aircraft and aviation
  ground support equipment at fixed-land or sea-based locations. The theater aviation maintenance sustainment
  group assists deploying aviation operational units in port operations.
  Army Air And Missile Defense Command
  3-81. The Army air and missile defense command is a headquarters element responsible for the command
  of all subordinate Army air and missile defense units as well as the army air and missile defense coordinator
  for the land component. When required by the geographic combatant command, the Army air and missile
  defense command will be attached to the theater army, if not already assigned. Air and missile defense units
  in an AOR are assigned or attached to the Army air and missile defense command.
  3-82. The Army air and missile defense command (AAMDC) commander has several responsibilities.
  These include command of all subordinate Army air and missile defense units; army air and missile defense
  coordinator for the land component and ARFOR; and deputy area air defense commander (known as AADC)
  if designated. The AAMDC commander has overall responsibility for planning Army air and missile defense
  operations in support of the JFC. To accomplish these duties, the AAMDC task-organizes and assigns
  missions to subordinate brigades. It also provides liaison elements to the joint force air component, joint force
  land component, and joint special operations task force to integrate air and missile defense operations. If the
  AAMDC is not located in the JOA, the ADA Brigade Commander (if one is deployed) may serve as the
  deputy area air defense commander. That brigade takes responsibility for planning and providing liaison to
  the JFLCC, area air defense commander, and joint force air component commander.
  Theater Engineer Command
  3-83. The theater engineer command (TEC) is a command and control headquarters. The command provides
  theater-wide engineer support as well as engineer support to forces deployed in a JOA. The Army currently
  has two theater engineer commands; both reside in the Reserve Component. The engineer command
  supervises geospatial support, construction, real property maintenance activities, line of communications
  support, engineer sustainment management, and base development. The command has primary responsibility
  for theater infrastructure repair or development. The command supports Department of State or host-nation
  efforts to restore essential services and aids in infrastructure development. Subordinate units of the command
  may include tailored engineer brigades, battalions, and specialized field force engineers such as forward
  engineer support teams (known as FESTs), contingency real estate support teams, and environmental support
  teams. Within the supervisory role of theater-wide geospatial support, the TEC serves as the in-theater
  interface with the theater aligned geospatial planning cell. The TEC facilitates the theater common
  operational picture by providing the Standard and Shareable Geospatial Foundation (SSGF) to organizations
  operating in the theater; and providing updates to the theater geospatial database from data collected in the
  theater to the GPC for incorporation into the Standard and Shareable Geospatial Foundation (SSGF).
  3-84. The theater engineer command typically serves as the senior engineer headquarters for the theater army
  and all assigned or attached engineer brigades and other engineer units. When directed, it may also command
  engineers from other Services and multinational forces and provide oversight of contracted construction
  engineers. The theater engineer command provides peacetime training and support of military engagement
  for their supported respective combatant commanders. The command also coordinates closely with the senior
  contract construction agents in the JOA. (See FM 3-34 for more information on the theater engineer
  command.)