TM 55-1510-222-10 ON switch is located in the center of the rheostat.  The light is capable of producing a red or white spotlight by adjusting a diaphragm, located in front of the light.  To remove the light from the stationary position, pull down on the light.  The light is connected to the light housing by an 11 inch coiled cord that extends to approximately 50   inches.      Power   for   the   utility   lights   is   provided through  the  5-ampere  circuit  breaker  placarded  CABIN LIGHTS, in the overhead circuit breaker panel. (4) Cabin  door  latching  mechanism light.    An  annunciator  is  provided  to  check  the  cabin door   latching   mechanism.      It   is   controlled   by   a   red pushbutton     switch     located     adjacent     to     the     round observation   window,   which   is   just   above   the   second step. 2-77. EMERGENCY LIGHTING. a. Description.      An   independent,   battery operated,  emergency  lighting  system  is  installed.    The system  is  actuated  automatically  by  shock,  such  as  a forced landing.  It provides adequate lighting inside and outside  the  fuselage  to  permit  the  occupants  to  read instruction placards and locate exits.  An inertia switch, when    subjected    to    a    2    G    (minimum)    shock,    will illuminate:  interior lights in the cockpit; forward and aft cabin areas; exterior lights aft of the emergency exit and aft   of   the   cabin   door.      The   battery   power   source   is automatically recharged by the aircraft electrical system. b. Operation. An emergency lights override  switch,  located  in  the  overhead  control  panel (fig.  2-13),  is  provided  to  turn  the  system  off  if  it  is accidentally     actuated.          The     switch     is     placarded EMERGENCY OFF - RESET - AUTO - TEST.  Should the  system  accidentally  actuate,  the  emergency  lights will  illuminate.    Placing  the  switch  in  the  momentary OFF/RESET  position  will  extinguish  the  lights.    To  test the system, place the switch in the TEST position.  The lights   should   illuminate.      Moving   the   switch   to   the OFF/RESET  position  will  turn  the  system  off  and  reset it. Section XI.  FLIGHT INSTRUMENTS 2-78. PITOT AND STATIC SYSTEM. a. Description.  The pitot and static system (fig.    2-31)    provides    static    pressure    for:        pilot    and copilot's  airspeed  indicators,  copilot  altimeter,  air  data computer,  pilot  and  copilot's  vertical  speed  indicators: and   ram   air   to   the   airspeed   indicators   and   air   data computer.  This system consists of two pitot masts (one located  on  each  side  of  the  lower  portion  of  the  nose), static air pressure ports in the aircraft's exterior skin on each  side  of  the  aft  fuselage,  and  associated  system plumbing.        The    pitot    mast    is    protected    from    ice formation by internal electric heating elements. b. Alternate Static Air Source. An alternate  static  air  line,  which  terminates  just  aft  of  the rear  pressure  bulkhead,  provides  a  source  of  static  air for the pilot's instruments, in the event of source failure from  the  pilot's  static  air  line.    A  control  on  the  pilot's subpanel   placarded   PILOTS   STATIC   AIR   SOURCE, may   be   actuated   to   select   either   the   NORMAL   or ALTERNATE air source by a two position selector valve. The   valve   is   secured   in   the   NORMAL   position   by   a spring clip. 2-79. TURN-AND-SLIP INDICATORS. Turn-and-slip  indicators  are  installed  separately on  the  pilot  and  copilot  sides  of  the  instrument  panel (fig.     2-14).          These     indicators     are     gyroscopically operated.  The DC powered gyros are protected by the 5-ampere   circuit   breakers   placarded   TURN   &   SLIP PILOT   or   COPILOT,   located   in   the   overhead   circuit breaker panel (fig. 2-6).  The inclinometer portion of the turn and slip indicator operates independently of the DC circuit. 2-80. AIRSPEED INDICATORS. Two, identical, independent, airspeed indicators are installed separately on the pilot and copilot sides of the   instrument   panel   (fig.   2-14).      These   indicators require no electrical power for operation.  The indicator dials  are  calibrated  in  knots  from  40  to  300.    A  striped pointer  automatically  displays  the  maximum  allowable airspeed at the aircraft's present altitude. 2-81. PILOT'S SERVOED ALTIMETER. The  pilot's  altimeter  is  located  in  the  upper  left side of the instrument panel (fig. 2-14).  It is a servoed unit,  displaying  aircraft  altitude  as  provided  by  the  air data  computer  (ADC).    The  barometric  pressure  is  set manually  with  the  BARO  knob,  located  on  the  pilot's altimeter, and is displayed in units of inches of mercury and  millibars,  on  the  baro  counters.    Once  the  BARO knob  is  manually  adjusted,  the  barometric  pressure  is inputted to the air data computer.  The ADC is supplied outside air temperature, receiving 2-75