PART I-DESCRIPTIVE

     8.   Relighting pushbutton

          The igniter plugs are used to relight the engine in flight
          by pressing the relight button on the inboard side the
          H.P. cock with the ignition switch on.

     9.   Throttle control

    (a)   The throttle lever (21) moves in a quadrant which
          incorporates a reheat gate forward of the normal full
          throttle position.

     (b)  Incorporated in the throttle handle is the GGS manual
          ranging twist-grip, together with the flaps inching switch
          and press-to-transmit button.

     10.  Reheat system

     (a)  The purpose of the system is to augment engine thrust
          by burning injected fuel in the jet-pipe. The temperature
          of the exhaust gases and hence their efflux speed from the
          jet-pipe nozzle is thereby increased, giving added thrust.

     (b)  When reheat is selected (see para. 12), the reheat igniter
          is energized for about 30 seconds and simultaneously
          causes solenoids to open two cocks. One cock permits
          fuel from the engine H.P. system to flow to a reheat
          pilot burner where it is lit by the igniter: the other cock
          allows air from the engine compressor to start up the
          reheat pump. As fuel pressure from the reheat pump
          builds up a pressure switch energizes a solenoid to open
          the reheat H.P. fuel cock allowing fuel to pass to the
          main reheat burner where it is ignited by the pilot burner
          flame.

     (c)  The pressure switch also energizes a second solenoid on
          the jet-pipe nozzle control valve. Air from the com-
          pressor then operates four ram jacks which open the jet
          pipe "eyelids" thereby increasing the final nozzle area.

     (d)  After about 30 seconds a time switch operates to cut off
          current to the reheat igniter.

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