TM 55-1510-219-10 2-22.  POWER LEVERS. CAUTION Moving the power levers into reverse  range  without  the  engines running   may   result   in   damage   to the reverse linkage mechanism. Two   power   levers   are   located   on   the   control pedestal (fig.  2-11).  These levers regulate power in the reverse,   idle,   and   forward   range,   and   operate   so   that forward    movement    increases    engine    power.        Power control   is   accomplished   through   adjustment   of   the   N1 speed    governor    in    the    fuel    control    unit.        Power    is increased  when  Ni  RPM  is  increased.    The  power  levers also  control  propeller  reverse  pitch.    Distinct  movement (pulling up and then aft on the power lever) by the pilot is required  for  reverse  thrust.    Placarding  beside  the  lever travel  slots  reads  POWER.    Upper  lever  travel  range  is designated  INCR  (increase),  supplemented  by  an  arrow pointing  forward.    Lower  travel  range  is  marked  IDLE, LIFT  and  REVERSE.    A  placard  below  the  lever  slots reads:      CAUTION   REVERSE   ONLY   WITH   ENGINES RUNNING. 2-23.  CONDITION LEVERS. Two condition levers are located on the control pedestal (fig.  2-11).  Each lever starts and stops the fuel supply,  and  controls  the  idle  speed  for  its  engine.    The levers  have  three  placarded  positions:    FUEL  CUTOFF, LO   IDLE,   and   HIGH   IDLE.      In   the   FUEL   CUTOFF position, the condition lever controls the cutoff function of its  engine-mounted  fuel  control  unit.    From  LO  IDLE  to HIGH IDLE, they control the governors of the fuel control units  to  establish  minimum  fuel  flow  levels.    LO  IDLE position sets the fuel flow rate to attain 52 to 55% (at sea level) minimum NI and HIGH IDLE position sets the rate to   attain   70%   minimum   NI.      The   power   lever   for   the corresponding  engine  can  select  NI  from  the  respective idle setting to maximum power.  An increase in low idle Ni will be experienced at high field elevation. 2-24.  FRICTION LOCK KNOBS. Four   friction   lock   knobs,   placarded   FRICTION LOCK, are provided on the control pedestal (fig.  211) to adjust  friction  drag  against  the  engine  power,  propeller RPM, and fuel condition levers.  These knobs prevent the levers from creeping.  When rotated clockwise, each knob increases   the   friction   that   opposes   movement   of   the affected lever.  Counterclockwise movement of the knob decreases friction. 2-25.  ENGINE FIRE DETECTION SYSTEM. a. Description.  A flame surveillance system is installed on each engine to detect external engine fire and provide  alarm  to  the  pilot.    Both  nacelles  are  monitored, each   having   a   control   amplifier   and   three   detectors. Electrical     wiring     connects     all     sensors     and     control amplifiers  to  DC  power  and  to  the  cockpit  visual  alarm units.  In each nacelle, one detector monitors the forward nacelle, a second monitors the upper accessory area, and a  third  the  lower  accessory  area.    Fire  emits  an  infrared radiation    that    will    be    sensed    by    the    detector    which monitors the area of origin.  Radiation exposure activates the relay circuit of a control amplifier which causes signal power   to   be   sent   to   cockpit   warning   systems.      An activated  surveillance  system  will  return  to  the  standby state   after   the   fire   is   out.      The   system   includes   a functional  test  switch  and  has  circuit  protection  through the   FIRE   DETR   circuit   breaker.      Warning   of   internal nacelle   fire   is   provided   as   follows:      the   red   MASTER WARNING lights on the glareshield illuminate accompanied by the illumination of a red warning light in the   appropriate   fire   control   T-handle   placarded   FIRE PULL (fig.  2-28).  Fire detector circuits are protected by a single  5-ampere  circuit  breaker,  placarded  FIRE  DETR, located on the overhead circuit breaker panel (fig.  2-26). b. Fire  Detection  System  Test  Switch.    One rotary switch placarded FIRE PROTECTION TEST on the copilot's   subpanel   is   provided   to   test   the   engine   fire detection  system.    Before  checkout,  battery  power  must be on and the FIRE DETR circuit breaker must be closed. Switch  position  DETR  1,  checks  the  area  forward  of  the air intake of each nacelle, including circuits to the cockpit alarm  and  indication  devices.    Switch  position  DETR  2, checks the circuits for the upper accessory compartment of  each  nacelle.    Switch  position  DETR  3,  checks  the circuits   for   the   lower   accessory   compartment   of   each nacelle.    Each  numbered  switch  position  will  initiate  the cockpit indications previously described. c. Erroneous Fire Detection System Indications.        During    ground    test    of    the    engine    fire detection system, an erroneous indication of system fault my  be  encountered  if  an  engine  cowling  is  not  closed properly,   or   if   the   aircraft   is   headed   toward   a   strong external  light  source.    In  this  circumstance,  change  the aircraft heading to enable a valid system check. 2-26.  ENGINE FIRE EXTINGUISHER SYSTEM. a. Description.    The  fire  extinguisher  system utilizes    an    explosive    squib    and    valve    which,    when 2-25