TM 55-1510-219-10 Synchronized control wheel steering Indicated airspeed hold mode All-angle adaptive capture for VOR, LOC, and LOC B/C Attitude display Heading display Mode selection indicators Elevator trim indicator System integrity warning flags Automatic yaw damping Turn and slip indicator The   flight   director   and   autopilot   have   a   common computer  system.    When  the  autopilot  is  engaged,  the flight  control  system  controls  the  aircraft  and  the  pilot monitors  the  flight  path  by  observing  the  information displayed on the pilot's horizon reference indicator (HRI) and  the  pilot's  horizontal  situation  indicator  (HSI)  (flight director system indicators). Autopilot/flight  director  commands  are  selected  at the  autopilot  mode  selector  panel  (fig.    3-18)  on  the pilot's side of the instrument panel.  Manual roll rate and pitch  commands  are  inserted  at  the  autopilot  pitch-turn panel    (fig.        3-21).        Autopilot    operational    status    is indicated    by    the    autopilot/flight    director    annunciator positioned  above  the  pilot's  horizon  reference  indicator on   the   instrument   panel   (fig.      2-28).      Two   autopilot switches  are  also  provided  on  each  control  wheel  (fig. 2-16).    One  switch  is  placarded  PITCH  SYNC  &  CWS (pitch  synchronize  and  control  wheel  steering),  and  the other    is    placarded    DISC    TRIM/AP    YD    (disconnect trim/autopilot yaw damp). Power    for    the    system    is    provided    through    a 10ampere   AP   PWR   circuit   breaker   located   on   the overhead circuit breaker panel (fig.  2-26). b. Controls  and  Indicators.    The  following  controls and indicators are provided for operation of the system. (1) Instrument Panel (Pilot's). (a)    Autopilot Mode select panel (fig.  3- 18).  The autopilot/flight director commands are selected by the autopilot mode selector. Selection is accomplished  by  pressing  the  face  of  the  appropriate push-on/push-off  switch.    The  lateral  modes  are  HDG, NAV, APPR and B/C.  When not in a lateral mode, the flight  director  command  bars  are  biased  out  of  view. The  vertical  modes  are  ALT,  IAS,  and  pitch  (all  hold modes).    If  a  vertical  mode  is  not  selected,  the  pitch hold mode is automatically operational. Selection    of    a    mode    causes    the    legend    of    that pushbutton switch to illuminate.  The self-test switch on the  lower  right  of  the  autopilot  control  panel  acts  as  a lamp   test   when   depressed.      For   operation   at   night, overall  illumination  of  the  autopilot  mode  selector  and switches is adjusted by the PILOT'S INSTRUMENT light control. CONTROL/ FUNCTION INDICATOR HDG switch Engages  heading mode.  Com- mands aircraft to acquire the heading indicated by heading marker on pilot's HSI. NAV switch Engages navigation mode.  VOR- I/VOR-2 or TACAN selected, commands aircraft to intercept and track VOR radial selected by course knob on pilot's HSI. INS selected, commands aircraft to track steering signals from INS system.  Intercept of approx- imately 45°  and tracking will be computed by the INS system. NOTE APPR cannot be selected with INS selected. APPR switch Engages approach mode.  Com- mands aircraft to intercept and track ILS inbound course. ALT switch Engages  altitude  hold  mode. Commands aircraft to maintain pressure altitude. IAS switch Engages indicated airspeed hold mode.  Commands aircraft to maintain airspeed. B/C switch Engages backcourse mode.  Com- mands aircraft to intercept back course ILS. ENG-DIS switch Controls coupling of the auto- matic pilot. ENG Engages  autopilot  and  illumi- nates engaged indicator. DIS Disengages autopilot and illumi- nates disengaged indicator. TRIM UP Illuminates when  autopilot  is indicator   driving   trim   servo   in   up direction. TRIM DN Illuminates  when  autopilot  is indicator driving trim servo in down di- rection. 3-34