PART III - HANDLING

            tanks, resulting in a slow decrease of the reading of the
            fuel contents gauge.  When the fuel flow has been
            reduced to less than 4,000 lb./hr. the level of the internal
            tanks will be slowly restored.  By the time the drop tanks
            are empty, the readings of the contents gauge and the
            totalizer will be about equal and will decrease together
            thereafter, both showing approximately the same
            reading.
       (v)  The contents gauge must always be regarded as the
            master instrument in so far as fuel contents is concerned,
            the totalizer being used only for checking.

       50.  Engine handling
       
       (i)  Whenever the throttle is opened, the initial movement
            must be slow until the engine is definitely accelerating.
            Thereafter the throttle may be opened rapidly at any
            altitude up to 40,000 feet.  Above this height all throttle
            movements must be made with care to avoid the pos-
            sibility of a compressor stall and possible flame
            extinction.
       (ii) While the engine is running on the main fuel system
            the emergency system should be switched OFF, other-
            wise if the throttle ia opened rapidly, the emergency
            system will override the normal system causing a com-
            pressor stall or flame extinction.
       (iii)Rapid acceleration to full power immediately after
            starting a cold engine will usually result in excessive
            j.p.t.
       (iv) Compressor stall is recognised by a pulsating roaring
            noise accompanied by heavy vibration coupled with little
            or no increase in r.p.m. and a rapid rise in j.p.t.  The
            throttle must be closed until these conditions disappear
            and a slower acceleration attempted.
       (v)  Engine noise and roughness may occur in flight especially
            when at high power above 15,000 feet; this can usually
            be overcome by changing the r.p.m.  If the roughness
            continues irrespective of height and r.p.m., a mechanical
            failure is the probable cause and a landing should be
            made.

       51.  Engine starting
                   
            NOTE.-Extreme care must be taken when moving the
                  throttle while starting, until idling r.p.m. are
                  obtained.  Small movements result in large
                  changes in fuel flow and excessive temperatures
                  may easily result.  It is recommended that until

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