2. 3. 4. 5. 6. 7. mode   selector.   If   VS   or   IAS   are not   selected,   the   pitch   wheel works  as  described  above.  The pitch  wheel  is  always  disabled during  a  coupled  glide  slope. BANK  LIMIT  PUSHBUTTON/ ANNUNCIATOR SWITCH. Selection  of  the  Bank  Limit  mode on   the   autopilot   controller   pro- vides  a  lower  maximum  bank angle  while  in  the  Heading  Select mode.  LOW  will  illuminate  on the  Bank  Limit  switch.  The  lower bank  limit  is  inhibited  and  LOW is  extinguished  during  NAV  mode captures.  If  Heading  Select  is again   engaged,   Bank   Limit   will again   be   illuminated.   Pressing Bank  Limit  when  illuminated  will return   autopilot   to   normal   bank limits. SOFT  RIDE  PUSHBUTTON/ ANNUNCIATOR   SWITCH.   Soft ride  reduces  autopilot  gains  while still  maintaining  stability  in  rough air.  This  mode  may  be  used  with a n y   F l i g h t   D i r e c t o r   m o d e selected. TURN  KNOB.  Rotation  of  the turn  knob  out  of  detent  results  in a  roll  command.  The  roll  angle  is proportional   to   and   in   the   direc- tion  of  the  turn  knob  rotation.  the turn  knob  must  be  in  detent  (cen- ter   position)   before   the   autopilot can   be   engaged.   Rotation   of   the turn  knob  cancels  any  other  previ- ously  selected  lateral  mode. YAW  DAMP  SWITCH.  When the   autopilot   is   not   engaged,   the yaw  damper  may  be  utilized  by depressing  the  YD  ENGAGE pushbutton. AP   ENGAGE   PUSHBUTTON/ ANNUNCIATOR   SWITCH.   The AP  ENGAGE  switch  is  used  to engage  the  autopilot.  Engaging  the autopilot  automatically  engages the  yaw  damper.  The  autopilot may  be  engaged  with  the  airplane in  any  reasonable  attitude. ELEV   TRIM   ANNUNCIATORS. The   elevator   trim   annunciator indicates  UP  or  DN  when  a sustained   signal   is   being   applied to the elevator servo. The TM  55-1510-221-10 annunciator should not be illuminated   when   engaging   the autopilot. (3.)   Autopilot   Disengagement.   The   autopi- lot  is  normally  disengaged  by  momentarily  depress- ing  the  control  wheel  AP  DISC  switch.  The  autopilot may  however  be  disengaged  by  any  of  the  following: 1. 2. 3. 4. 5. 6. 7. 8. Actuation  of  the  control  wheel  AP DISC   button.   Disengagement   is confirmed  by  5  flashes  of  the  AP ENG   annunciator. Pressing   the   respective   vertical gyro  FAST  ERECT  button. Actuation  of  respective  compass INCREASE-DECREASE   switch. Selection   of   Go-Around   mode. Disengagement   is   confirmed   by the  AP  ENG  annunciator  flashing 5  times  and  illumination  of  the GA  and  YD  ENG  annunciators. Pulling   the   autopilot   CONTROL &  AFCS  DIRECT  circuit  breaker. Pressing the autopilot   AP ENGAGE   pushbutton. Actuation   of   the   manual   electric trim. Any  of  the  following  malfunctions will   cause   the   autopilot   to   auto- matically  disengage: a. Vertical  gyro  failure. b.   Directional   gyro   failure. c. Autopilot   power   or   circuit failure. d.   Torque   limiter   failure. NOTE Disengaging   under   any   of   the   previous four   conditions   will   illuminate   the   AP DISC   annunciator   and   the   MASTER WARNING  light.  Pressing  the  control wheel  AP  DISC  switch  will  extinguish  the AP   DISC   annunciator. (4.)  Pitch  Sync  &  Control  Wheel  Steering (CWS). The CWS push button located on the control wheel  (fig.  2-17)  allows  the  pilot  to  manually  change aircraft   attitude,   altitude,   vertical   speed   and/or   air- speed  without  disengaging  the  autopilot.  After  com- pleting  the  manual  maneuver,  the  CWS  pushbutton is   released,   and   the   autopilot   will   automatically 3-43