roundel jsl spacer hunter1
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                           PART 1-DESCRIPTIVE

   (ii) The fuel from all the permanent tanks passes to a col-
        lector box which also acts as a negative "g" reservoir
        and incorporates negative "g" valves affording a fuel
        supply for ten seconds inverted flight.  The tanks, which
        are not pressurised, are vented to atmosphere.  A satis-
        factory delivery pressure at altitude is ensured by a
        booster pump, which is immersed in the fuselage tank.

   (iii)The flow of fuel from the wing tanks to the fuse-
 	lage tank is controlled by a float valve mounted at the
 	top of the fuselage tank.  The wing drop tanks are pres-
        surised from the engine blower casing.  Mod. 591 incor-
        porates a reducing valve from each wing drop tank, thus
        ensuring that fuel can be drawn from one tank should the
        other be holed.
 	        
   (iv) Fuel from the booster pump passes through a low pressure
        cock and a filter, to an engine-drive pump capable of
        maintaining a constant fuel pressure throughout the
        power range.  An aneroid-operated barostat, fitted to the
        delivery line of this pump, controls the fuel supply by
        returning surplus fuel to the collector box as height is
        gained.  The engine r.p.m. therefore remain substantially
        constant at any selected throttle opening.  From the
        engine-driven pump fuel passes to the throttle (fuel con-
        trol valve) and the high pressure cock.  A minimum pres-
        sure valve is fitted in parallel with the throttle.  This
        ensures that at altitude, regardless of the throttle setting,
        sufficient pressure will be maintained at the burner ring
        to prevent flame extinction, providing the booster pump
        is ON.  Maximum pressure at the burner ring is con-
        trolled by an overspeed governor.  From the overspeed
        governor fuel passes to the starter valve, and the line is
        tapped to supply a fuel accumulator.  The purpose of the
        accumulator is to provide a fixed quantity of fuel at a
        known pressure at the moment of starting.  When starting
        the engine, a dump valve drains any fuel present in the
        system, before the pressure builds up; when shutting
        down the engine it prevents free fuel draining into the
        combustion chambers after the pressure has fallen.
 	        
   2.   Fuel contents gauges
 	   
   (i)  Contents gauges
 	   
        Five fuel contents gauges (38) are mounted below the
        centre instrument panel.  The top left- and right-hand

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