roundel jsl spacer hunter1
previous thumbnails next

PART III-HANDLING


     (f)  If the fuel pressure indicator shows white (fuel pressure
          low) when the belly tank is being used, switch the over-
          ride switch to TAKE-OFF immediately.

     53.  Engine handling

     (a)  The acceleration control unit (A.C.U.) ensures optimum
          acceleration under normal flight conditions at low
          altitude but becomes progressively less effective with
          increase in height. Except in cases of necessity throttle
AL3/57     movements should be smooth and progressive.  Damage to the
          engine may result if the throttle is closed too rapidly at high I.A.S.

     (b)  When the compressor is hot the engine will not accelerate
          from low r.p.m., (below about 3,500). These conditions
          can only be reached if the throttle is closed after a period
          at high or moderate power at low speed (e.g. the
          approach to land). At high speed this will not occur as
          the r.p.m. will not fall low enough until the speed has
          dropped off by which time the compressor will have
          cooled. It may be found, particularly in hot weather,
          that the engine will not accelerate when the throttle is
          opened to taxy away at the end of the landing run. In
          this case the throttle should be closed and opened again
          to assist the engine to pick up but careful watch must be
          kept on j.p.t.

          WARNING.-Except in cases of extreme emergency no
                   attempt should be made to overshoot once
                   the throttle has been fully closed for landing.

     (c)  When temperatures at high altitude are below normal a
          combination of high r.p.m. and low forward speed can
          produce a compressor stall which is accompanied by one
          or more loud bangs. With the compressor in a stalled
          condition the engine will idle at lower r.p.m. than is
          normal at high altitude and a slight buzzing noise may
          be discernible, in this condition the engine will not
          accelerate when the throttle is opened. If this occurs the
          throttle should be closed at once to prevent excessive
          j.p.t. and speed increased until the compressor unstalls
          and buzzing ceases.  Up to 8,000 feet may be lost before
          the compressor will unstall and it should not be assumed
          that a flame out has occurred unless the r.p.m. are
          substantially below 3,000.  If flame out has occurred the

48

previous thumbnails next