PART I-DESCRIPTIVE

     3.  Main fuel system

     (a)  Fuel from all tanks is fed under low pressure, by
          immersed booster pumps, to a collector box and then to
          two pipe lines, one to the engine-driven H.P. fuel pumps
          and one to the reheat system through the reheat L.P.
          cock. (See paras. 5 and 12.)

     (b)  Fuel in the belly tank is automatically used first under
          normal conditions. When this tank is empty its booster
          pump is automatically switched off by a float-operated
          switch and the internal tanks pumps are simultaneously
          switched on.

     (c)  For short periods of inverted flying, fuel is provided by
          the fuel recuperator in the centre tank. This is a
          flexible bag inside a cylindrical tank. When the aircraft
          is inverted no pressure supply is available from the
          booster pumps and the fuel from the recuperator is forced
          out by air pressure from the engine acting on the bag.
          When normal flight is resumed, the pressure from the
          booster pumps is greater than the air pressure and the
          recuperator is automatically refilled.

     (d)  An air pressurizing system tapped from the engine com-
          pressor, maintains a pressure of 3 lb./sq. in. in all tanks
          to prevent boiling and to assist in fuel transfer.

     (e)  A magnetic indicator (59) on the starboard instrument
          panel shows white if fuel delivery pressure from the
          collector box drops appreciably below normal.

     (f)  A panel of five magnetic indicators (58), one for each
          internal tank, is fitted beside the pressure indicator.
          Each indicator shows white only when fuel flow from
          its associated tank is below normal. A cancelling device
          ensures that the indicators do not show white when their
          associated tanks are empty. A magnetic indicator (63)
          below the starboard instrument panel shows white when
          fuel is not flowing from the belly tank.

     4.   Fuel booster pumps
     
     (a)  Eight booster pumps are fitted, one in each fuselage tank,
          two in each wing tank and one in the belly tank.

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