TM 1-1510-224-10 NOTE The  avionics  power  relay  is  normally hot.    Pulling  the  AVIONICS  MASTER CONTR   circuit   breaker   will   remove power    to    the    relay,    thus    allowing electrical    power    to    the    associated busses. i. BAT  FEED  FAULT  Annunciator  Illuminated.    If the  BAT  FEED  FAULT  caution  annunciator  illuminates, perform the following: (1) BATTERY switch - RESET, then  ON. 9-28.  EMERGENCY DESCENT. The  following  procedure  assumes  the  structural  integrity of  the  aircraft  and  smooth  flight  conditions.    If  structural integrity  is  in  doubt,  limit  speed  as  much  as  possible, reduce   rate   of   descent   if   necessary,   and   avoid   high maneuvering   loads.      For   emergency   descent,   perform the follow- ing: 1. POWER levers - IDLE. 2. PROP levers -  HIGH RPM. 3. Flaps - APPROACH. 4. Gear - DN. 5. Airspeed - 179 KIAS (0.472 Mach) maximum. NOTE Windshield defogging may be required. 9-29.  FLIGHT CONTROL MALFUNCTIONS. Use   the   following   procedures,   as   applicable,   for   flight control malfunctions. a. Autopilot,. Emergency Disconnection. The autopilot   can   be   disengaged   by   any   of   the   following methods: 1. Pressing the AP & YD/RIM DISC switch. 2. Pressing the  AP  ENGAGE  pushbutton  on the autopilot controller. 3. Pressing   the   GO-AROUND   switch   (yaw damper will remain on). 4. Pulling the AP CONTR and AFCS DIRECT circuit breakers. 5. Setting AVIONICS MASTER POWER switch to the off (aft) position. 6. Setting  aircraft   MASTER  SWITCH   to   the OFF position. 7. Setting the  AUTO PLT power switch to off position. b. Yaw  Damp  Emergency  Disconnection.  The yaw damp    can    be    disengaged    by    any    of    the    following methods: 1. Pressing the AP & YD/TRIM DISC switch. 2. Pressing the  AP  ENGAGE  pushbutton  on the autopilot controller. 3. Setting the RUDDER BOOST/YAW CONTROL    TEST    switch    to    the    YAW CONTROL TEST position. 4. Pulling the  AP CONTR circuit breaker. 5. Pulling the RUDDER BOOST circuit breaker. 6. Setting AVIONICS MASTER POWER switch to the off (aft) position. 7. Setting    aircraft    MASTER    switch    to    the OFF position. 8. Setting the AUTO PLT power switch to off. c. Unscheduled  Rudder  Boost  Activation.    Rudder boost    operation    without    a    large    variation    of    power between    engines    indicates    a    failure    of    the    system. Perform the following: 1. AP  &  YD/RIM  DISC   switch  -  Disconnect and hold (hold to first level). (2) RUDDER BOOST switch - OFF. 3. RUDDER   BOOST   circuit   breaker   -   Pull (provided    that    rudder    boost    does    not deactivate). 4. AP & YD/TRIM DISC switch - Release. (5) Yaw      damper   -   Reengage   (if   RUDDER BOOST circuit breaker is not pulled). d. Unscheduled   Electric   Trim.        In    the    event    of unscheduled electric elevator trim, perform the following: 1. ELEV TRIM switch - OFF. 2. ELEC TRIM circuit breaker - Pull. 9-13