Description (AMM 34-31-02)

A- An integrated flight system accessory unit is located in electronic equipment rack E1-3. The unit contains solid state relays, solenoid operated relays, and printed circuits for signal conditioning and interface between the navigation systems and the flight instruments. In addition, the unit contains numerous relays, time delay gates, a circuit interrupter and other components used for interconnecting the DFCS system.

B- The integrated flight system accessory unit circuits associated with the VOR/ILS navigation system consist of the diodes across the coils of the transfer relays; six solid state relays, four relays for inhibiting the VOR/ILS self-tests when the autopilot is operating in an approach mode and two to control the ground return for energizing ILS relays No. 1 and No. 2; and two solenoid operated mode relays for inhibiting the RDDMI VOR bearing displays when the DME and FMC systems are operating in the agility mode.